Send Android accessibility event when object location changes.

Note that the LOCATION_CHANGED event isn't explicitly handled, it just gets mapped to a WINDOW_CONTENT_CHANGED event on Android.

BUG=407871

Review URL: https://codereview.chromium.org/510513003

Cr-Commit-Position: refs/heads/master@{#292216}

content/browser/accessibility/browser_accessibility.h

@@ -65,7 +65,7 @@ class CONTENT_EXPORT BrowserAccessibility {
   virtual bool IsNative() const;
 
   // Called when the location changed.
-  virtual void OnLocationChanged() const {}
+  virtual void OnLocationChanged() {}
 
   // Return true if this object is equal to or a descendant of |ancestor|.
   bool IsDescendantOf(BrowserAccessibility* ancestor);

content/browser/accessibility/browser_accessibility_android.cc

@@ -55,6 +55,10 @@ bool BrowserAccessibilityAndroid::IsNative() const {
   return true;
 }
 
+void BrowserAccessibilityAndroid::OnLocationChanged() {
+  manager()->NotifyAccessibilityEvent(ui::AX_EVENT_LOCATION_CHANGED, this);
+}
+
 bool BrowserAccessibilityAndroid::PlatformIsLeaf() const {
   if (InternalChildCount() == 0)
     return true;

content/browser/accessibility/browser_accessibility_android.h

@@ -15,6 +15,7 @@ class BrowserAccessibilityAndroid : public BrowserAccessibility {
   // Overrides from BrowserAccessibility.
   virtual void OnDataChanged() OVERRIDE;
   virtual bool IsNative() const OVERRIDE;
+  virtual void OnLocationChanged() OVERRIDE;
 
   virtual bool PlatformIsLeaf() const OVERRIDE;
 

content/browser/accessibility/browser_accessibility_win.cc

@@ -3176,7 +3176,7 @@ bool BrowserAccessibilityWin::IsNative() const {
   return true;
 }
 
-void BrowserAccessibilityWin::OnLocationChanged() const {
+void BrowserAccessibilityWin::OnLocationChanged() {
   manager()->ToBrowserAccessibilityManagerWin()->MaybeCallNotifyWinEvent(
       EVENT_OBJECT_LOCATIONCHANGE, unique_id_win());
 }

content/browser/accessibility/browser_accessibility_win.h

@@ -105,7 +105,7 @@ BrowserAccessibilityWin
   CONTENT_EXPORT virtual void NativeAddReference() OVERRIDE;
   CONTENT_EXPORT virtual void NativeReleaseReference() OVERRIDE;
   CONTENT_EXPORT virtual bool IsNative() const OVERRIDE;
-  CONTENT_EXPORT virtual void OnLocationChanged() const OVERRIDE;
+  CONTENT_EXPORT virtual void OnLocationChanged() OVERRIDE;
 
   //
   // IAccessible methods.