Revert of Use labels to display views tab titles.

ui/views/controls/label.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef UI_VIEWS_CONTROLS_LABEL_H_
 #define UI_VIEWS_CONTROLS_LABEL_H_
 
 #include <string>
 #include <vector>
 
 #include "base/compiler_specific.h"
 #include "base/gtest_prod_util.h"
 #include "base/strings/string16.h"
 #include "third_party/skia/include/core/SkColor.h"
 #include "ui/gfx/font_list.h"
 #include "ui/gfx/text_constants.h"
 #include "ui/views/view.h"
 
 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[];
 
   // The padding for the focus border when rendering focused text.
   static const int kFocusBorderPadding;
 
   Label();
   explicit Label(const base::string16& text);
   Label(const base::string16& text, const gfx::FontList& font_list);
   virtual ~Label();
@@ skipping 32 matching lines @@
 
   // Sets the shadow blur. Default is zero.
   void set_shadow_blur(double shadow_blur) { shadow_blur_ = shadow_blur; }
 
   // Disables shadows.
   void ClearEmbellishing();
 
   // 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_;
   }
 
   // Get or set the distance in pixels between baselines of multi-line text.
   // Default is 0, indicating the distance between lines should be the standard
   // one for the label's text, font list, and platform.
   int line_height() const { return line_height_; }
   void SetLineHeight(int height);
 
   // Get or set if the label text can wrap on multiple lines; default is false.
@@ skipping 76 matching lines @@
   virtual void OnPaint(gfx::Canvas* canvas) OVERRIDE;
   virtual void OnNativeThemeChanged(const ui::NativeTheme* theme) OVERRIDE;
 
  private:
   // These tests call CalculateDrawStringParams in order to verify the
   // calculations done for drawing text.
   FRIEND_TEST_ALL_PREFIXES(LabelTest, DrawSingleLineString);
   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
   // the label's 'obscured' status into account.
   void SetTextInternal(const base::string16& text);
 
   void Init(const base::string16& text, const gfx::FontList& font_list);
 
   void RecalculateColors();
 
@@ skipping 37 matching lines @@
   mutable bool text_size_valid_;
   int line_height_;
   bool is_multi_line_;
   bool is_obscured_;
   bool allow_character_break_;
   gfx::ElideBehavior elide_behavior_;
   gfx::HorizontalAlignment horizontal_alignment_;
   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_;
   SkColor disabled_shadow_color_;
 
   // Space between text and shadow.
   gfx::Point shadow_offset_;
 
   // Should a shadow be drawn behind the text?
   bool has_shadow_;
 
   // Indicates the level of shadow blurring. Default is zero.
   double shadow_blur_;
 
   // The halo color drawn around the text if it is not transparent.
   SkColor halo_color_;
 
   // The cached heights to avoid recalculation in GetHeightForWidth().
   mutable std::vector<gfx::Size> cached_heights_;
   mutable int cached_heights_cursor_;
 
   DISALLOW_COPY_AND_ASSIGN(Label);
 };
 
 }  // namespace views
 
 #endif  // UI_VIEWS_CONTROLS_LABEL_H_