Allow virtual keyboard window to access audio stream and speech api for voice input

ash/shell/shell_delegate_impl.cc

Index: ash/shell/shell_delegate_impl.cc
diff --git a/ash/shell/shell_delegate_impl.cc b/ash/shell/shell_delegate_impl.cc
index a3092873b963340914764e2324af555fbac44120..0ae565837ce26a219d360f7bda9d41f07d4d6202 100644
--- a/ash/shell/shell_delegate_impl.cc
+++ b/ash/shell/shell_delegate_impl.cc
@@ -40,6 +40,12 @@ class DummyKeyboardControllerProxy : public keyboard::KeyboardControllerProxy {
     return Shell::GetInstance()->input_method_filter()->input_method();
   }
 
+  virtual void RequestAudioInput(content::WebContents* web_contents,
+      const content::MediaStreamRequest& request,
+      const content::MediaResponseCallback& callback) OVERRIDE {
+    return;
+  }
+
   DISALLOW_COPY_AND_ASSIGN(DummyKeyboardControllerProxy);
 };