Implement eliding/truncating at end in RenderText

ui/gfx/render_text.h

Index: ui/gfx/render_text.h
diff --git a/ui/gfx/render_text.h b/ui/gfx/render_text.h
index 8696d690560e6fddc28da3a59740d725c88a8e57..308b6737064740c7952b264dfa394a3905080267 100644
--- a/ui/gfx/render_text.h
+++ b/ui/gfx/render_text.h
@@ -27,6 +27,7 @@
 #include "ui/gfx/shadow_value.h"
 #include "ui/gfx/size_f.h"
 #include "ui/gfx/text_constants.h"
+#include "ui/gfx/text_elider.h"
 #include "ui/gfx/vector2d.h"
 
 class SkCanvas;
@@ -227,6 +228,12 @@ class GFX_EXPORT RenderText {
   // WARNING: Only use this for system limits, it lacks complex text support.
   void set_truncate_length(size_t length) { truncate_length_ = length; }
 
+  // Elides the text to fit in |display_rect| according to the specified
+  // |elide_behavior|. |ELIDE_IN_MIDDLE| is not supported.
+  // If both truncate and elide are specified, the shorter of the two will be
+  // applicable.
+  void SetElideBehavior(ElideBehavior elide_behavior);
+
   const Rect& display_rect() const { return display_rect_; }
   void SetDisplayRect(const Rect& r);
 
@@ -535,6 +542,8 @@ class GFX_EXPORT RenderText {
   FRIEND_TEST_ALL_PREFIXES(RenderTextTest, ApplyColorAndStyle);
   FRIEND_TEST_ALL_PREFIXES(RenderTextTest, ObscuredText);
   FRIEND_TEST_ALL_PREFIXES(RenderTextTest, RevealObscuredText);
+  FRIEND_TEST_ALL_PREFIXES(RenderTextTest, ElidedText);
+  FRIEND_TEST_ALL_PREFIXES(RenderTextTest, ElidedObscuredText);
   FRIEND_TEST_ALL_PREFIXES(RenderTextTest, TruncatedText);
   FRIEND_TEST_ALL_PREFIXES(RenderTextTest, TruncatedObscuredText);
   FRIEND_TEST_ALL_PREFIXES(RenderTextTest, GraphemePositions);
@@ -556,6 +565,10 @@ class GFX_EXPORT RenderText {
   // Updates |layout_text_| if the text is obscured or truncated.
   void UpdateLayoutText();
 
+  // Elides |text| to fit in the |display_rect_| with given |elide_behavior_|.
+  // See ElideText in ui/gfx/text_elider.cc for reference.
+  base::string16 ElideText(const base::string16& text);
+
   // Update the cached bounds and display offset to ensure that the current
   // cursor is within the visible display area.
   void UpdateCachedBoundsAndOffset();
@@ -628,6 +641,9 @@ class GFX_EXPORT RenderText {
   // The maximum length of text to display, 0 forgoes a hard limit.
   size_t truncate_length_;
 
+  // The behavior for eliding or truncating.
+  ElideBehavior elide_behavior_;
+
   // The obscured and/or truncated text that will be displayed.
   base::string16 layout_text_;