[temporary M30 fix] Disable dragging tabs with web contents modal dialogs displayed

chrome/browser/ui/views/tabs/tab_strip_controller.h

Index: chrome/browser/ui/views/tabs/tab_strip_controller.h
diff --git a/chrome/browser/ui/views/tabs/tab_strip_controller.h b/chrome/browser/ui/views/tabs/tab_strip_controller.h
index 4e53c1bdeb07e3e878ee8ffdfeb0929d39a77695..3a11ae0f672de516dc014a81c03e96c07fc1c939 100644
--- a/chrome/browser/ui/views/tabs/tab_strip_controller.h
+++ b/chrome/browser/ui/views/tabs/tab_strip_controller.h
@@ -99,6 +99,10 @@ class TabStripController {
   // Invoked if the layout type might have changed.
   virtual void LayoutTypeMaybeChanged() = 0;
 
+  // Returns true if the tab at the given index is showing a web view modal
+  // dialog.
+  virtual bool IsTabShowingWebViewModalDialog(int index) = 0;
+
   // Notifies controller that the user started dragging this tabstrip's tabs.
   virtual void OnStartedDraggingTabs() = 0;