Replace return button with close button on custom tab toolbar

chrome/android/java/src/org/chromium/chrome/browser/toolbar/ToolbarLayout.java

Index: chrome/android/java/src/org/chromium/chrome/browser/toolbar/ToolbarLayout.java
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/toolbar/ToolbarLayout.java b/chrome/android/java/src/org/chromium/chrome/browser/toolbar/ToolbarLayout.java
index d8b9541f3db316e038f9eddfc50ad7689bdf3f2d..e9531ce0e5e8f7ebba249abcd6089da3f9a2115c 100644
--- a/chrome/android/java/src/org/chromium/chrome/browser/toolbar/ToolbarLayout.java
+++ b/chrome/android/java/src/org/chromium/chrome/browser/toolbar/ToolbarLayout.java
@@ -264,8 +264,12 @@ abstract class ToolbarLayout extends FrameLayout implements Toolbar {
     @Override
     public void setBookmarkClickHandler(OnClickListener listener) { }
 
-    @Override
-    public void setCustomTabReturnClickHandler(OnClickListener listener) { }
+
+    /**
+     * Sets the OnClickListener to notify when the close button is pressed in a custom tab.
+     * @param listener The callback that will be notified when the close button is pressed.
+     */
+    public void setCustomTabCloseClickHandler(OnClickListener listener) { }
 
     /**
      * Gives inheriting classes the chance to update the visibility of the
@@ -334,6 +338,11 @@ abstract class ToolbarLayout extends FrameLayout implements Toolbar {
      */
     protected void onPrimaryColorChanged() { }
 
+    /**
+     * Sets the icon resource that the close button in the toolbar (if any) should show.
+     */
+    public void setCloseButtonImageResource(int iconRes) { }
+
     @Override
     public void addCustomActionButton(Bitmap buttonSource, OnClickListener listener) { }