Use extension rather than local names in ModuleExtensionMetadata

ModuleExtensionMetadata incorrectly identified repos by their local names rather than the names used by the generating extension, which resulted in incorrect fixup warnings when supplying keyword arguments to `use_repo`.

Closes #18528.

PiperOrigin-RevId: 536386347
Change-Id: I4368b0dcdc28d6b2827b74b3b0b73c31a0215c0f

Author: fmeum

src/main/java/com/google/devtools/build/lib/bazel/bzlmod/ModuleExtensionMetadata.java

@@ -188,7 +188,7 @@ private static Optional<Event> generateFixupMessage(
             .collect(toImmutableSet());
     var actualImports =
         rootUsages.stream()
-            .flatMap(usage -> usage.getImports().keySet().stream())
+            .flatMap(usage -> usage.getImports().values().stream())
             .filter(repo -> !actualDevImports.contains(repo))
             .collect(toImmutableSet());
 

src/test/java/com/google/devtools/build/lib/bazel/bzlmod/ModuleExtensionResolutionTest.java

@@ -1603,13 +1603,23 @@ public void extensionMetadata() throws Exception {
         "bazel_dep(name='ext', version='1.0')",
         "bazel_dep(name='data_repo',version='1.0')",
         "ext = use_extension('@ext//:defs.bzl', 'ext')",
-        "use_repo(ext, 'direct_dep', 'indirect_dep', 'invalid_dep')",
+        "use_repo(",
+        "  ext,",
+        "  'indirect_dep',",
+        "  'invalid_dep',",
+        "  my_direct_dep = 'direct_dep',",
+        ")",
         "ext_dev = use_extension('@ext//:defs.bzl', 'ext', dev_dependency = True)",
-        "use_repo(ext_dev, 'direct_dev_dep', 'indirect_dev_dep', 'invalid_dev_dep')");
+        "use_repo(",
+        "  ext_dev,",
+        "  'indirect_dev_dep',",
+        "  'invalid_dev_dep',",
+        "  my_direct_dev_dep = 'direct_dev_dep',",
+        ")");
     scratch.file(workspaceRoot.getRelative("BUILD").getPathString());
     scratch.file(
         workspaceRoot.getRelative("data.bzl").getPathString(),
-        "load('@direct_dep//:data.bzl', direct_dep_data='data')",
+        "load('@my_direct_dep//:data.bzl', direct_dep_data='data')",
         "data = direct_dep_data");
 
     registry.addModule(