Set AllowOverlappingViews for history overlay

chrome/browser/ui/cocoa/browser_window_controller.h

Index: chrome/browser/ui/cocoa/browser_window_controller.h
diff --git a/chrome/browser/ui/cocoa/browser_window_controller.h b/chrome/browser/ui/cocoa/browser_window_controller.h
index 7311745771e0abbafa73c3034455886024620b99..9d21eef1f2033f26a79a12a5c307d1810a1d128e 100644
--- a/chrome/browser/ui/cocoa/browser_window_controller.h
+++ b/chrome/browser/ui/cocoa/browser_window_controller.h
@@ -162,6 +162,9 @@ class WebContents;
   // The offset between the bottom of the toolbar and web contents. This is used
   // to push the web contents below the bookmark bar.
   CGFloat toolbarToWebContentsOffset_;
+
+  // The number of history overlay views being shown.
+  NSUInteger historyOverlayCount_;
 }
 
 // A convenience class method which gets the |BrowserWindowController| for a
@@ -341,10 +344,21 @@ class WebContents;
          returnCode:(NSInteger)code
             context:(void*)context;
 
+// Updates the bookmark bar visibility based on the instant overlay state.
 - (void)updateBookmarkBarStateForInstantOverlay;
 
+// Called when the find bar visibility changes. This is used to update the
+// allowOverlappingViews state.
 - (void)onFindBarVisibilityChanged;
 
+// Called when a history overlay is shown. This is used to update the
+// allowOverlappingViews state.
+- (void)onHistoryOverlayShown;
+
+// Called when a history overlay is hidden. This is used to update the
+// allowOverlappingViews state.
+- (void)onHistoryOverlayHidden;
+
 @end  // @interface BrowserWindowController