bluetooth: Initial simple mock content::WebBluetoothImpl.

content/public/test/layouttest_support.h

Index: content/public/test/layouttest_support.h
diff --git a/content/public/test/layouttest_support.h b/content/public/test/layouttest_support.h
index 23354ff4f8405f475fd2106b83cb57e378ab0710..4f8994a553fadf5a75f45a7b924d44bf016f3cd5 100644
--- a/content/public/test/layouttest_support.h
+++ b/content/public/test/layouttest_support.h
@@ -93,6 +93,9 @@ void SetDeviceScaleFactor(RenderView* render_view, float factor);
 // Set the device color profile associated with the profile |name|.
 void SetDeviceColorProfile(RenderView* render_view, const std::string& name);
 
+// Change the bluetooth test data while running a layout test.
+void SetBluetoothMockDataSetForTesting(const std::string& name);
+
 // Enables or disables synchronous resize mode. When enabled, all window-sizing
 // machinery is short-circuited inside the renderer. This mode is necessary for
 // some tests that were written before browsers had multi-process architecture