Disabled pinch zooming in non-browser Aura windows.

chrome/browser/ui/browser.h

Index: chrome/browser/ui/browser.h
diff --git a/chrome/browser/ui/browser.h b/chrome/browser/ui/browser.h
index 42dcc85f819c3b1ec6d5b017f78894c9e6d6c86b..38072027403cef70c8dcb7e16b4bb9f1713a0f29 100644
--- a/chrome/browser/ui/browser.h
+++ b/chrome/browser/ui/browser.h
@@ -62,6 +62,10 @@ class TabStripModel;
 class TabStripModelDelegate;
 struct WebApplicationInfo;
 
+namespace blink {
+class WebGestureEvent;
+}
+
 namespace chrome {
 class BrowserCommandController;
 class FastUnloadController;
@@ -441,6 +445,9 @@ class Browser : public TabStripModelObserver,
   virtual void HandleKeyboardEvent(
       content::WebContents* source,
       const content::NativeWebKeyboardEvent& event) OVERRIDE;
+  virtual bool PreHandleGestureEvent(
+      content::WebContents* source,
+      const blink::WebGestureEvent& event) OVERRIDE;
   virtual void OverscrollUpdate(int delta_y) OVERRIDE;
   virtual void ShowValidationMessage(content::WebContents* web_contents,
                                      const gfx::Rect& anchor_in_root_view,