Zoom Extension API (chrome)

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 5dac267aa171184e86e28f6bb189395073ba2e8e..67ac7c1cec2e3f5ec309c84cb55d531ab152f8c6 100644
--- a/chrome/browser/ui/browser.h
+++ b/chrome/browser/ui/browser.h
@@ -753,6 +753,11 @@ class Browser : public TabStripModelObserver,
 
   // Assorted utility functions ///////////////////////////////////////////////
 
+  // Sets/Clears this browser object as an observer on helpers of the web
+  // contents.
+  void SetAsObserver(content::WebContents* web_contents);

[sky, 2014/06/24 16:23:41]

The name and this function and description imply something very generic. Yet the
implementation is just about zoom. Since the implementation of these functions
is just a one liner I don't see any value in them.

Maybe I'm missing something, but AFAICT the only changes you should need in
browser.cc are to change 2195 (old) to something like:

if (delegate)
  ZoomController::FromWebContents(web_contents)->AddObserver(delegate);
else
  ZoomController::FromWebContents(web_contents)->RemoveObserver(this);

The latter is slightly unfortunate. It could be clarified by making the function
take a boolean instead of a delegate.

[wjmaclean, 2014/06/24 18:04:07]

It was the latter case that caused me to create the separate functions, but if
it's ok to change to using a boolean then that makes it clear that the delegate
is only ever 'this' and we are setting/clearing.

+  void ClearAsObserver(content::WebContents* web_contents);
+
   // Sets the specified browser as the delegate of the WebContents and all the
   // associated tab helpers that are needed.
   void SetAsDelegate(content::WebContents* web_contents, Browser* delegate);