Changes to content/ to facilitate new zoom extension API

content/public/browser/web_contents.h

Index: content/public/browser/web_contents.h
diff --git a/content/public/browser/web_contents.h b/content/public/browser/web_contents.h
index d84774fdcc36387d2c332fd439e548dec969559f..bb06b595af4eb3d3e12fc40e509e40ffd0d09324 100644
--- a/content/public/browser/web_contents.h
+++ b/content/public/browser/web_contents.h
@@ -18,6 +18,7 @@
 #include "content/public/browser/page_navigator.h"
 #include "content/public/browser/save_page_type.h"
 #include "content/public/browser/web_ui.h"
+#include "content/public/common/page_zoom.h"
 #include "content/public/common/stop_find_action.h"
 #include "ipc/ipc_sender.h"
 #include "third_party/skia/include/core/SkColor.h"
@@ -424,6 +425,10 @@ class WebContents : public PageNavigator,
   virtual void SetClosedByUserGesture(bool value) = 0;
   virtual bool GetClosedByUserGesture() const = 0;
 
+  // Gets the zoom mode for this WebContents, which determines the behavior of
+  // zoom changes.
+  virtual ZoomMode GetZoomMode() const = 0;
+
   // Gets the zoom level for this tab.
   virtual double GetZoomLevel() const = 0;
 
@@ -494,10 +499,18 @@ class WebContents : public PageNavigator,
   // removed since we can then embed iframes in different processes.
   virtual bool IsSubframe() const = 0;
 
+  // Sets the flag indicating whether zooming will have default behavior.
+  virtual void SetZoomMode(ZoomMode mode) = 0;
+
   // Sets the zoom level for the current page and all BrowserPluginGuests
   // within the page.
   virtual void SetZoomLevel(double level) = 0;
 
+  // Optionally provide a callback function to be called after the zoom change
+  // has completed.
+  virtual void SetZoomLevel(double level,
+                            const base::Callback<void(void)>& callback) = 0;

[jam, 2014/04/10 21:45:45]

why exactly does the extensions api need this callback?

also note that you can subscribe to zoom level changes through HostZoomMap's
callbacks (AddZoomLevelChangedCallback). have you looked into using that instead
of this? this is how chrome updates its UI

+
   // Finds text on a page.
   virtual void Find(int request_id,
                     const base::string16& search_text,