Implement the Instant extended API startMargin, endMargin, and rtl properties and the onmarginchang…

chrome/browser/instant/instant_loader.h

Index: chrome/browser/instant/instant_loader.h
diff --git a/chrome/browser/instant/instant_loader.h b/chrome/browser/instant/instant_loader.h
index 3837b87997eaadbe2a79ba4f47a75b88b2225371..2d72251edaf407464e90dcc1beaa81cfb8333d1d 100644
--- a/chrome/browser/instant/instant_loader.h
+++ b/chrome/browser/instant/instant_loader.h
@@ -60,10 +60,15 @@ class InstantLoader : public content::NotificationObserver {
   // is taken as the exact query (no prediction is made).
   void Update(const string16& user_text, bool verbatim);
 
-  // Tells the preview page of the bounds of the omnibox dropdown (in screen
+  // Tells the preview page of the bounds of the omnibox popup (in screen
   // coordinates). This is used by the page to offset the results to avoid them
   // being covered by the omnibox dropdown.
-  void SetOmniboxBounds(const gfx::Rect& bounds);
+  void SetPopupBounds(const gfx::Rect& bounds);
+
+  // Tells the preview page what size margins to use. Both |start| and |end|
+  // are offsets from the start edge of the page delimiting the horizontal
+  // bounds of the page text area.
+  void SetMarginSize(int start, int end);
 
   // Tells the preview page about the available autocomplete results.
   void SendAutocompleteResults(