Missing parsing of 'displayAlign' from <style> tags from Ttml subtitles

### Version

Media3 main branch

### More version details

Issue present in main 1.8.0-beta01 branch

Example of ttml subtitles where 'displayAlign' is not correctly parsed from existing TtmlParser.java class:
```
<?xml version="1.0" encoding="UTF-8"?><tt xml:lang="it" xmlns="http://www.w3.org/ns/ttml" xmlns:ttm="http://www.w3.org/ns/ttml#metadata" xmlns:tts="http://www.w3.org/ns/ttml#styling" xmlns:smpte="http://www.smpte-ra.org/schemas/2052-1/2010/smpte-tt" ><head>
<smpte:information smpte:mode="Enhanced" />
<styling>
<style xml:id="backgroundStyle" tts:fontFamily="proportionalSansSerif" tts:textAlign="center" tts:origin="0% 66%" tts:extent="100% 33%" tts:backgroundColor="rgba(0,0,0,0)" tts:displayAlign="center" />
<style xml:id="speakerStyle" style="backgroundStyle" tts:color="white" tts:textOutline="black 1px" tts:backgroundColor="transparent" />
<style xml:id="textStyle" style="speakerStyle" tts:color="white" tts:textOutline="none" tts:backgroundColor="black" />
</styling><layout>
<region xml:id="full" tts:origin="0% 0%" tts:extent="100% 100%" tts:zIndex="1" />
<region xml:id="speaker" style="speakerStyle" tts:zIndex="1" />
<region xml:id="background" style="backgroundStyle" tts:zIndex="0" />
</layout>
</head><body>
<div>
<p region="speaker" begin="00:19:32.640" end="00:19:36.160"><span style="textStyle">Lorem ipsum dolor sit amet consectetur adipiscing elit<br/>Quisque faucibus ex sapien vitae pellentesque sem placerat</span></p>
<p region="speaker" begin="00:19:36.320" end="00:19:38.560"><span style="textStyle">Ad litora torquent per conubia nostra inceptos himenaeos.</span></p>
<p region="speaker" begin="00:19:45.880" end="00:19:48.800"><span style="textStyle">Quisque faucibus ex sapien vitae pellentesque sem placerat</span></p>
<p region="speaker" begin="00:19:52.040" end="00:19:55.040"><span style="textStyle">Ad litora torquent per conubia nostra inceptos himenaeos.</span></p>
</div>
</body></tt>
 
```

'displayAlign' is currently only parsed from 'region' and not from 'style' xml tags. Then subtitles may not be aligned vertically correctly.


Idea to fix that:

1) Add these setter/getter into TtmlStyle class:
```
...
@Nullable private String displayAlign;
@Nullable private String parentStyleId;
...
public TtmlStyle setDisplayAlign(@Nullable String displayAlign) {
  this.displayAlign = displayAlign;
  return this;
}

  @Nullable
public String getDisplayAlign() {
  return displayAlign;
}

public TtmlStyle setParentStyleId(@Nullable String parentStyleId) {
  this.parentStyleId = parentStyleId;
  return this;
}

@Nullable
public String getParentStyleId() {
  return parentStyleId;
}
```

2. Add parsing of 'displayAlign' and 'style' attributes from 'style'  tags in TtmlParser class
```
private static @PolyNull TtmlStyle parseStyleAttributes(
      XmlPullParser parser, @PolyNull TtmlStyle style) {
...
case TtmlNode.ATTR_STYLE:
  style = createIfNull(style).setParentStyleId(attributeValue);
  break;
case TtmlNode.ATTR_TTS_DISPLAY_ALIGN:
  style = createIfNull(style).setDisplayAlign(attributeValue);
  break;
....
```

3. Retrieve 'displayAlign' from 'style' or parentStyle if not present from 'region' in TtmlParser class
```
....
@Cue.AnchorType int lineAnchor = Cue.ANCHOR_TYPE_START;
@Nullable
String displayAlign =
    XmlPullParserUtil.getAttributeValue(xmlParser, TtmlNode.ATTR_TTS_DISPLAY_ALIGN);
if (displayAlign == null) {
  String styleId = XmlPullParserUtil.getAttributeValue(xmlParser, TtmlNode.ATTR_STYLE);
  if (styleId != null) {
    TtmlStyle style = globalStyles.get(styleId);
    if (style != null) {
      displayAlign = style.getDisplayAlign();
    }
  }
}
if (displayAlign == null) {
  String styleId = XmlPullParserUtil.getAttributeValue(xmlParser, TtmlNode.ATTR_STYLE);
  if (styleId != null) {
    TtmlStyle style = globalStyles.get(styleId);
    if (style != null) {
      String parentStyleId = style.getParentStyleId();
      if (parentStyleId != null) {
        TtmlStyle parentStyle = globalStyles.get(parentStyleId);
        if (parentStyle != null) {
          displayAlign = parentStyle.getDisplayAlign();
        }
      }
    }
  }
}

if (displayAlign != null) {
  switch (Ascii.toLowerCase(displayAlign)) {
    case "center":
      lineAnchor = Cue.ANCHOR_TYPE_MIDDLE;
      line += height / 2;
      break;
    case "after":
      lineAnchor = Cue.ANCHOR_TYPE_END;
      line += height;
      break;
    default:
      // Default "before" case. Do nothing.
      break;
  }
}
....
```

That's it.


### Devices that reproduce the issue

All

### Devices that do not reproduce the issue

None

### Reproducible in the demo app?

Yes

### Reproduction steps

Mock for example a stream with this ttml:
```
<?xml version="1.0" encoding="UTF-8"?><tt xml:lang="it" xmlns="http://www.w3.org/ns/ttml" xmlns:ttm="http://www.w3.org/ns/ttml#metadata" xmlns:tts="http://www.w3.org/ns/ttml#styling" xmlns:smpte="http://www.smpte-ra.org/schemas/2052-1/2010/smpte-tt" ><head>
<smpte:information smpte:mode="Enhanced" />
<styling>
<style xml:id="backgroundStyle" tts:fontFamily="proportionalSansSerif" tts:textAlign="center" tts:origin="0% 66%" tts:extent="100% 33%" tts:backgroundColor="rgba(0,0,0,0)" tts:displayAlign="center" />
<style xml:id="speakerStyle" style="backgroundStyle" tts:color="white" tts:textOutline="black 1px" tts:backgroundColor="transparent" />
<style xml:id="textStyle" style="speakerStyle" tts:color="white" tts:textOutline="none" tts:backgroundColor="black" />
</styling><layout>
<region xml:id="full" tts:origin="0% 0%" tts:extent="100% 100%" tts:zIndex="1" />
<region xml:id="speaker" style="speakerStyle" tts:zIndex="1" />
<region xml:id="background" style="backgroundStyle" tts:zIndex="0" />
</layout>
</head><body>
<div>
<p region="speaker" begin="00:19:32.640" end="00:19:36.160"><span style="textStyle">Lorem ipsum dolor sit amet consectetur adipiscing elit<br/>Quisque faucibus ex sapien vitae pellentesque sem placerat</span></p>
<p region="speaker" begin="00:19:36.320" end="00:19:38.560"><span style="textStyle">Ad litora torquent per conubia nostra inceptos himenaeos.</span></p>
<p region="speaker" begin="00:19:45.880" end="00:19:48.800"><span style="textStyle">Quisque faucibus ex sapien vitae pellentesque sem placerat</span></p>
<p region="speaker" begin="00:19:52.040" end="00:19:55.040"><span style="textStyle">Ad litora torquent per conubia nostra inceptos himenaeos.</span></p>
</div>
</body></tt>
```

### Expected result

In the above example 'speakerStyle' should be positioned at line value 0.825, but is placed at 0.66 because the current parsing does not parse parent style and displayAlign from style xml tags.

### Actual result

In the above example 'speakerStyle' should be positioned at line value 0.825, but is placed at 0.66 because the current parsing does not parse parent style and displayAlign from style xml tags.

### Media

```
<?xml version="1.0" encoding="UTF-8"?><tt xml:lang="it" xmlns="http://www.w3.org/ns/ttml" xmlns:ttm="http://www.w3.org/ns/ttml#metadata" xmlns:tts="http://www.w3.org/ns/ttml#styling" xmlns:smpte="http://www.smpte-ra.org/schemas/2052-1/2010/smpte-tt" ><head>
<smpte:information smpte:mode="Enhanced" />
<styling>
<style xml:id="backgroundStyle" tts:fontFamily="proportionalSansSerif" tts:textAlign="center" tts:origin="0% 66%" tts:extent="100% 33%" tts:backgroundColor="rgba(0,0,0,0)" tts:displayAlign="center" />
<style xml:id="speakerStyle" style="backgroundStyle" tts:color="white" tts:textOutline="black 1px" tts:backgroundColor="transparent" />
<style xml:id="textStyle" style="speakerStyle" tts:color="white" tts:textOutline="none" tts:backgroundColor="black" />
</styling><layout>
<region xml:id="full" tts:origin="0% 0%" tts:extent="100% 100%" tts:zIndex="1" />
<region xml:id="speaker" style="speakerStyle" tts:zIndex="1" />
<region xml:id="background" style="backgroundStyle" tts:zIndex="0" />
</layout>
</head><body>
<div>
<p region="speaker" begin="00:19:32.640" end="00:19:36.160"><span style="textStyle">Lorem ipsum dolor sit amet consectetur adipiscing elit<br/>Quisque faucibus ex sapien vitae pellentesque sem placerat</span></p>
<p region="speaker" begin="00:19:36.320" end="00:19:38.560"><span style="textStyle">Ad litora torquent per conubia nostra inceptos himenaeos.</span></p>
<p region="speaker" begin="00:19:45.880" end="00:19:48.800"><span style="textStyle">Quisque faucibus ex sapien vitae pellentesque sem placerat</span></p>
<p region="speaker" begin="00:19:52.040" end="00:19:55.040"><span style="textStyle">Ad litora torquent per conubia nostra inceptos himenaeos.</span></p>
</div>
</body></tt>
```

### Bug Report

- [ ] You will email the zip file produced by `adb bugreport` to android-media-github@google.com after filing this issue.

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Missing parsing of 'displayAlign' from <style> tags from Ttml subtitles #2559

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Missing parsing of 'displayAlign' from <style> tags from Ttml subtitles #2559

Description

Version

More version details

Devices that reproduce the issue

Devices that do not reproduce the issue

Reproducible in the demo app?

Reproduction steps

Expected result

Actual result

Media

Bug Report

Metadata

Metadata

Assignees

Labels

Type

Projects

Milestone

Relationships

Development

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