<webview>: Support zoom in WebUI

content/public/browser/web_contents.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CONTENT_PUBLIC_BROWSER_WEB_CONTENTS_H_
 #define CONTENT_PUBLIC_BROWSER_WEB_CONTENTS_H_
 
 #include <set>
 
 #include "base/basictypes.h"
@@ skipping 464 matching lines @@
                             bool is_favicon,
                             uint32_t max_bitmap_size,
                             const ImageDownloadCallback& callback) = 0;
 
   // Returns true if the WebContents is responsible for displaying a subframe
   // in a different process from its parent page.
   // TODO: this doesn't really belong here. With site isolation, this should be
   // removed since we can then embed iframes in different processes.
   virtual bool IsSubframe() const = 0;
 
+  // Sets the zoom level for the current main frame.

[nasko, 2014/01/06 21:58:40]

Is this for the main frame only or for the full document displaying in this
WebContents?

[Fady Samuel, 2014/01/08 19:42:43]

That depends on your definition of zoom. This zooms the main frame and all
subframes stay at 1.0 RELATIVE zoom. Guests are separate processes so we need to
update zoom there too. I add a small clarification in the comment.

+  virtual void SetZoomLevel(double level) = 0;
+
 #if defined(OS_ANDROID)
   CONTENT_EXPORT static WebContents* FromJavaWebContents(
       jobject jweb_contents_android);
   virtual base::android::ScopedJavaLocalRef<jobject> GetJavaWebContents() = 0;
 #endif  // OS_ANDROID
 
  private:
   // This interface should only be implemented inside content.
   friend class WebContentsImpl;
   WebContents() {}
 };
 
 }  // namespace content
 
 #endif  // CONTENT_PUBLIC_BROWSER_WEB_CONTENTS_H_