Simplify fetching title of tabs

The title of tabs in uBO is solely to have a better
presentation in the logger -- no other purpose.

This commit simplify keeping track of the titles, from
an active approach by directly querying it from tabs
whenever a change occurs, to a passive approach by
storing it when the title string become available in
some tab event handlers.

Author: gorhill

src/js/pagestore.js

@@ -328,7 +328,7 @@ const HostnameDetailsMap = class extends Map {
 /******************************************************************************/
 
 const PageStore = class {
-    constructor(tabId, context) {
+    constructor(tabId, details) {
         this.extraData = new Map();
         this.journal = [];
         this.journalTimer = undefined;
@@ -337,15 +337,15 @@ const PageStore = class {
         this.netFilteringCache = NetFilteringResultCache.factory();
         this.hostnameDetailsMap = new HostnameDetailsMap();
         this.counts = new CountDetails();
-        this.init(tabId, context);
+        this.init(tabId, details);
     }
 
-    static factory(tabId, context) {
+    static factory(tabId, details) {
         let entry = PageStore.junkyard.pop();
         if ( entry === undefined ) {
-            entry = new PageStore(tabId, context);
+            entry = new PageStore(tabId, details);
         } else {
-            entry.init(tabId, context);
+            entry.init(tabId, details);
         }
         return entry;
     }
@@ -354,7 +354,7 @@ const PageStore = class {
     //   The context is used to determine whether we report behavior change
     //   to the logger.
 
-    init(tabId) {
+    init(tabId, details) {
         const tabContext = µb.tabContextManager.mustLookup(tabId);
         this.tabId = tabId;
 
@@ -368,7 +368,6 @@ const PageStore = class {
         }
 
         this.tabHostname = tabContext.rootHostname;
-        this.title = tabContext.rawURL;
         this.rawURL = tabContext.rawURL;
         this.hostnameDetailsMap.reset();
         this.contentLastModified = 0;
@@ -385,13 +384,17 @@ const PageStore = class {
         this.frames = new Map();
         this.setFrameURL({ url: tabContext.rawURL });
 
+        if ( this.titleFromDetails(details) === false ) {
+            this.title = tabContext.rawURL;
+        }
+
         // Evaluated on-demand
         this._noCosmeticFiltering = undefined;
 
         return this;
     }
 
-    reuse(context) {
+    reuse(context, details) {
         // When force refreshing a page, the page store data needs to be reset.
 
         // If the hostname changes, we can't merely just update the context.
@@ -411,6 +414,7 @@ const PageStore = class {
             // URL changed, force a re-evaluation of filtering switch
             this.rawURL = tabContext.rawURL;
             this.setFrameURL({ url: this.rawURL });
+            this.titleFromDetails(details);
             return this;
         }
 
@@ -420,7 +424,7 @@ const PageStore = class {
             this.largeMediaTimer = null;
         }
         this.disposeFrameStores();
-        this.init(this.tabId, context);
+        this.init(this.tabId, details);
         return this;
     }
 
@@ -450,6 +454,14 @@ const PageStore = class {
         return null;
     }
 
+    titleFromDetails(details) {
+        if ( details instanceof Object && details.title !== undefined ) {
+            this.title = details.title;
+            return true;
+        }
+        return false;
+    }
+
     disposeFrameStores() {
         for ( const frameStore of this.frames.values() ) {
             frameStore.dispose();

src/js/start.js

@@ -69,7 +69,7 @@ const initializeTabs = async function() {
             if ( tab.discarded === true ) { continue; }
             const { id, url } = tab;
             µb.tabContextManager.commit(id, url);
-            µb.bindTabToPageStore(id);
+            µb.bindTabToPageStore(id, 'tabCommitted', tab);
             // https://github.com/chrisaljoudi/uBlock/issues/129
             //   Find out whether content scripts need to be injected
             //   programmatically. This may be necessary for web pages which

src/js/tab.js

@@ -884,7 +884,7 @@ vAPI.Tabs = class extends vAPI.Tabs {
         const { frameId, tabId, url } = details;
         if ( frameId === 0 ) {
             µb.tabContextManager.commit(tabId, url);
-            const pageStore = µb.bindTabToPageStore(tabId, 'tabCommitted');
+            const pageStore = µb.bindTabToPageStore(tabId, 'tabCommitted', details);
             if ( pageStore !== null ) {
                 pageStore.journalAddRootFrame('committed', url);
             }
@@ -910,7 +910,7 @@ vAPI.Tabs = class extends vAPI.Tabs {
         if ( !tab.url || tab.url === '' ) { return; }
         if ( !changeInfo.url ) { return; }
         µBlock.tabContextManager.commit(tabId, changeInfo.url);
-        µBlock.bindTabToPageStore(tabId, 'tabUpdated');
+        µBlock.bindTabToPageStore(tabId, 'tabUpdated', tab);
     }
 };
 
@@ -921,7 +921,7 @@ vAPI.tabs = new vAPI.Tabs();
 
 // Create an entry for the tab if it doesn't exist.
 
-µBlock.bindTabToPageStore = function(tabId, context) {
+µBlock.bindTabToPageStore = function(tabId, context, details = undefined) {
     this.updateToolbarIcon(tabId, 0b111);
 
     // Do not create a page store for URLs which are of no interests
@@ -935,8 +935,7 @@ vAPI.tabs = new vAPI.Tabs();
 
     // Tab is not bound
     if ( pageStore === undefined ) {
-        this.updateTitle(tabId);
-        pageStore = this.PageStore.factory(tabId, context);
+        pageStore = this.PageStore.factory(tabId, details);
         this.pageStores.set(tabId, pageStore);
         this.pageStoresToken = Date.now();
         return pageStore;
@@ -958,9 +957,8 @@ vAPI.tabs = new vAPI.Tabs();
     // Rebind according to context. We rebind even if the URL did not change,
     // as maybe the tab was force-reloaded, in which case the page stats must
     // be all reset.
-    pageStore.reuse(context);
+    pageStore.reuse(context, details);
 
-    this.updateTitle(tabId);
     this.pageStoresToken = Date.now();
 
     return pageStore;
@@ -1094,58 +1092,6 @@ vAPI.tabs = new vAPI.Tabs();
 
 /******************************************************************************/
 
-µBlock.updateTitle = (( ) => {
-    const tabIdToCount = new Map();
-    const delay = 499;
-
-    const updateTitle = async function(tabId) {
-        let count = tabIdToCount.get(tabId);
-        if ( count === undefined ) { return; }
-        tabIdToCount.delete(tabId);
-        const tab = await vAPI.tabs.get(tabId);
-        if ( tab instanceof Object === false || tab.discarded === true ) {
-            return;
-        }
-        const µb = µBlock;
-        const pageStore = µb.pageStoreFromTabId(tabId);
-        if ( pageStore === null ) { return; }
-        // Firefox needs this: if you detach a tab, the new tab won't have
-        // its rawURL set. Concretely, this causes the logger to report an
-        // entry to itself in the logger's tab selector.
-        // TODO: Investigate for a fix vAPI-side.
-        pageStore.rawURL = tab.url;
-        µb.pageStoresToken = Date.now();
-        // https://github.com/gorhill/uMatrix/issues/225
-        //   Sometimes title changes while page is loading.
-        const settled =
-            typeof tab.title === 'string' &&
-            tab.title !== '' &&
-            tab.title === pageStore.title;
-        pageStore.title = tab.title || tab.url || '';
-        if ( settled ) { return; }
-        if ( tabIdToCount.has(tabId) ) { return; }
-        count -= 1;
-        if ( count === 0 ) { return; }
-        tabIdToCount.set(tabId, count);
-        updateTitleAsync(tabId);
-    };
-
-    const updateTitleAsync = function(tabId) {
-        vAPI.setTimeout(( ) => { updateTitle(tabId); }, delay);
-    };
-
-    return function(tabId) {
-        if ( vAPI.isBehindTheSceneTabId(tabId) ) { return; }
-        const count = tabIdToCount.get(tabId);
-        tabIdToCount.set(tabId, 5);
-        if ( count === undefined ) {
-            updateTitleAsync(tabId);
-        }
-    };
-})();
-
-/******************************************************************************/
-
 // https://github.com/chrisaljoudi/uBlock/issues/455
 //   Stale page store entries janitor