Revert of Use labels to display views tab titles.

ui/views/controls/label.h

Index: ui/views/controls/label.h
diff --git a/ui/views/controls/label.h b/ui/views/controls/label.h
index 60dfba9165aeb1246c0bf2781775f0d42234a83e..9e2881dc69e93262bcc05df9703e7902d3887b19 100644
--- a/ui/views/controls/label.h
+++ b/ui/views/controls/label.h
@@ -18,9 +18,30 @@
 
 namespace views {
 
-// A view subclass that can display a string.
+/////////////////////////////////////////////////////////////////////////////
+//
+// Label class
+//
+// A label is a view subclass that can display a string.
+//
+/////////////////////////////////////////////////////////////////////////////
 class VIEWS_EXPORT Label : public View {
  public:
+  // The following enum is used to indicate whether using the Chrome UI's
+  // directionality as the label's directionality, or auto-detecting the label's
+  // directionality.
+  //
+  // If the label text originates from the Chrome UI, we should use the Chrome
+  // UI's directionality as the label's directionality.
+  //
+  // If the text originates from a web page, its directionality is determined
+  // based on its first character with strong directionality, disregarding what
+  // directionality the Chrome UI is.
+  enum DirectionalityMode {
+    USE_UI_DIRECTIONALITY = 0,
+    AUTO_DETECT_DIRECTIONALITY
+  };
+
   // Internal class name.
   static const char kViewClassName[];
 
@@ -73,17 +94,28 @@
   // Set the color of a halo on the painted text (use transparent for none).
   void set_halo_color(SkColor halo_color) { halo_color_ = halo_color; }
 
-  // Sets the horizontal alignment; the argument value is mirrored in RTL UI.
+  // Sets horizontal alignment. If the locale is RTL, and the directionality
+  // mode is USE_UI_DIRECTIONALITY, the alignment is flipped around.
+  //
+  // Caveat: for labels originating from a web page, the directionality mode
+  // should be reset to AUTO_DETECT_DIRECTIONALITY before the horizontal
+  // alignment is set. Otherwise, the label's alignment specified as a parameter
+  // will be flipped in RTL locales.
   void SetHorizontalAlignment(gfx::HorizontalAlignment alignment);
-  gfx::HorizontalAlignment GetHorizontalAlignment() const;
-
-  // Sets the directionality mode. The default value is DIRECTIONALITY_FROM_UI,
-  // which should be suitable for most text originating from UI string assets.
-  // Most text originating from web content should use DIRECTIONALITY_FROM_TEXT.
-  void set_directionality_mode(gfx::DirectionalityMode mode) {
+
+  gfx::HorizontalAlignment horizontal_alignment() const {
+    return horizontal_alignment_;
+  }
+
+  // Sets the directionality mode. The directionality mode is initialized to
+  // USE_UI_DIRECTIONALITY when the label is constructed. USE_UI_DIRECTIONALITY
+  // applies to every label that originates from the Chrome UI. However, if the
+  // label originates from a web page, its directionality is auto-detected.
+  void set_directionality_mode(DirectionalityMode mode) {
     directionality_mode_ = mode;
   }
-  gfx::DirectionalityMode directionality_mode() const {
+
+  DirectionalityMode directionality_mode() const {
     return directionality_mode_;
   }
 
@@ -180,7 +212,9 @@
   FRIEND_TEST_ALL_PREFIXES(LabelTest, DrawMultiLineString);
   FRIEND_TEST_ALL_PREFIXES(LabelTest, DrawSingleLineStringInRTL);
   FRIEND_TEST_ALL_PREFIXES(LabelTest, DrawMultiLineStringInRTL);
-  FRIEND_TEST_ALL_PREFIXES(LabelTest, DirectionalityFromText);
+  FRIEND_TEST_ALL_PREFIXES(LabelTest, AutoDetectDirectionality);
+
+  // Calls ComputeDrawStringFlags().
   FRIEND_TEST_ALL_PREFIXES(LabelTest, DisableSubpixelRendering);
 
   // Sets both |text_| and |layout_text_| to appropriate values, taking
@@ -238,9 +272,10 @@
   base::string16 tooltip_text_;
   // Whether to collapse the label when it's not visible.
   bool collapse_when_hidden_;
-  // Controls whether the directionality is auto-detected based on first strong
-  // directionality character or is determined by the application UI's locale.
-  gfx::DirectionalityMode directionality_mode_;
+  // The following member variable is used to control whether the
+  // directionality is auto-detected based on first strong directionality
+  // character or is determined by chrome UI's locale.
+  DirectionalityMode directionality_mode_;
 
   // Colors for shadow.
   SkColor enabled_shadow_color_;