Adds color, font size, text direction and text styles to the accessibility tree.

content/browser/accessibility/browser_accessibility.h

Index: content/browser/accessibility/browser_accessibility.h
diff --git a/content/browser/accessibility/browser_accessibility.h b/content/browser/accessibility/browser_accessibility.h
index 4f6b308619dc7983ae7d12d4d111ef9fa1b7dd7c..5d0c0a7c127e51ac0ea5be15d5e32bd099a8cd4a 100644
--- a/content/browser/accessibility/browser_accessibility.h
+++ b/content/browser/accessibility/browser_accessibility.h
@@ -112,18 +112,28 @@ class CONTENT_EXPORT BrowserAccessibility {
   // the role is WebAXRoleStaticText.
   gfx::Rect GetGlobalBoundsForRange(int start, int len) const;
 
-  // Searches in the given text and from the given offset until the start of
-  // the next or previous word is found and returns its position.
+  // Starting at the given offset, searches through this object's text until the
+  // beginning of the next or previous word is found and returns its position.
   // In case there is no word boundary before or after the given offset, it
   // returns one past the last character, i.e. the text's length.
   // If the given offset is already at the start of a word, returns the start
-  // of the next word if the search is forwards and the given offset if it is
-  // backwards.
+  // of the next word if the search is forwards. It returns the given offset
+  // if the search is backwards.
   // If the start offset is equal to -1 and the search is in the forwards
-  // direction, returns the start boundary of the first word.
+  // direction, it returns the start boundary of the first word.
   // Start offsets that are not in the range -1 to text length are invalid.
   int GetWordStartBoundary(
-      int start, ui::TextBoundaryDirection direction) const;
+      int offset, ui::TextBoundaryDirection direction) const;
+
+  // Starting at the given offset, searches either forwards or backwards through
+  // this object's text until it finds a change in text style. If the search is
+  // in the forwards direction, it returns the start of the next style span. If
+  // the search is in the backwards direction, it returns the start of the
+  // current style span.
+  // In case there is no style change after the given offset, it returns one
+  // past the last character, i.e. the text's length.
+  int GetStyleChangeBoundary(
+      int offset, ui::TextBoundaryDirection direction) const;
 
   // Returns the deepest descendant that contains the specified point
   // (in global screen coordinates).
@@ -265,6 +275,10 @@ class CONTENT_EXPORT BrowserAccessibility {
  protected:
   BrowserAccessibility();
 
+  // Returns the first deepest descendant that is an object with complete text
+  // information.
+  BrowserAccessibility* GetFirstTextLeaf() const;
+
   // The manager of this tree of accessibility objects.
   BrowserAccessibilityManager* manager_;
 
@@ -272,10 +286,27 @@ class CONTENT_EXPORT BrowserAccessibility {
   ui::AXNode* node_;
 
  private:
-  // Return the sum of the lengths of all static text descendants,
-  // including this object if it's static text.
+  // Returns true if the object is a leaf for purposes of text retrieval.
+  bool IsTextLeaf() const;
+
+  // Return the sum of the lengths of all text leaf descendants,
+  // including this object if it's a text leaf.
   int GetStaticTextLenRecursive() const;
 
+  // Returns the text leaf in which the given text offset lies and the offset
+  // at which the leaf's text starts.
+  BrowserAccessibility* GetTextLeafAtOffset(int offset, int* leaf_start_offset) const;
+
+  // Returns the last deepest descendant that is an object with complete text
+  // information.
+  BrowserAccessibility* GetLastTextLeaf() const;
+
+  // Returns the next object that is a text leaf, if any.
+  BrowserAccessibility* GetNextTextLeaf() const;
+
+  // Returns the previous object that is a text leaf, if any.
+  BrowserAccessibility* GetPreviousTextLeaf() const;
+
   // Similar to GetParent(), but includes nodes that are the host of a
   // subtree rather than skipping over them - because they contain important
   // bounds offsets.
@@ -286,6 +317,10 @@ class CONTENT_EXPORT BrowserAccessibility {
   // to the top of the web accessibility tree).
   gfx::Rect ElementBoundsToLocalBounds(gfx::Rect bounds) const;
 
+  // Returns true if the two objects have the same text style attributes.
+  static bool HaveSameStyle(BrowserAccessibility& object1,
+                            BrowserAccessibility& object2);
+
   DISALLOW_COPY_AND_ASSIGN(BrowserAccessibility);
 };