Merge 182576 to M26 beta branch.

chrome/browser/ui/views/extensions/extension_install_dialog_view.cc

Index: chrome/browser/ui/views/extensions/extension_install_dialog_view.cc
===================================================================
--- chrome/browser/ui/views/extensions/extension_install_dialog_view.cc	(revision 183257)
+++ chrome/browser/ui/views/extensions/extension_install_dialog_view.cc	(working copy)
@@ -95,6 +95,7 @@
 
  private:
   // views::DialogDelegateView:
+  virtual int GetDialogButtons() const OVERRIDE;
   virtual string16 GetDialogButtonLabel(ui::DialogButton button) const OVERRIDE;
   virtual int GetDefaultDialogButton() const OVERRIDE;
   virtual bool Cancel() OVERRIDE;
@@ -443,6 +444,14 @@
   GetWidget()->SetSize(GetWidget()->non_client_view()->GetPreferredSize());
 }
 
+int ExtensionInstallDialogView::GetDialogButtons() const {
+  int buttons = prompt_.GetDialogButtons();
+  // Simply having just an OK button is *not* supported. See comment on function
+  // GetDialogButtons in dialog_delegate.h for reasons.
+  DCHECK_GT(buttons & ui::DIALOG_BUTTON_CANCEL, 0);
+  return buttons;
+}
+
 string16 ExtensionInstallDialogView::GetDialogButtonLabel(
     ui::DialogButton button) const {
   switch (button) {