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

chrome/browser/instant/instant_tab.cc

Index: chrome/browser/instant/instant_tab.cc
diff --git a/chrome/browser/instant/instant_tab.cc b/chrome/browser/instant/instant_tab.cc
index 23085632d566e43e9a71465f0b23364935591c69..c57176fe62f429d991342598954492d605d4cad1 100644
--- a/chrome/browser/instant/instant_tab.cc
+++ b/chrome/browser/instant/instant_tab.cc
@@ -42,6 +42,10 @@ void InstantTab::UpOrDownKeyPressed(int count) {
   client_.UpOrDownKeyPressed(count);
 }
 
+void InstantTab::SetMarginSize(int start, int end) {
+  client_.SetMarginSize(start, end);
+}
+
 void InstantTab::SetSuggestions(
     const std::vector<InstantSuggestion>& suggestions) {
   InstantSupportDetermined(true);