Allow mouse-input to be enabled even if the plugin does not have keyboard focus.

remoting/client/plugin/chromoting_instance.cc

Index: remoting/client/plugin/chromoting_instance.cc
diff --git a/remoting/client/plugin/chromoting_instance.cc b/remoting/client/plugin/chromoting_instance.cc
index 83c25cb6d0e2e074507a1f7b2f509caea6644729..100004de093ba6b2c1708eb09863b6b27f89487a 100644
--- a/remoting/client/plugin/chromoting_instance.cc
+++ b/remoting/client/plugin/chromoting_instance.cc
@@ -360,6 +360,8 @@ void ChromotingInstance::HandleMessage(const pp::Var& message) {
     HandleAllowMouseLockMessage();
   } else if (method == "enableMediaSourceRendering") {
     HandleEnableMediaSourceRendering();
+  } else if (method == "sendMouseInputWhenUnfocused") {
+    HandleSendMouseInputWhenUnfocused();
   }
 }
 
@@ -964,6 +966,10 @@ void ChromotingInstance::HandleEnableMediaSourceRendering() {
   use_media_source_rendering_ = true;
 }
 
+void ChromotingInstance::HandleSendMouseInputWhenUnfocused() {
+  input_handler_.set_send_mouse_input_when_unfocused(true);
+}
+
 ChromotingStats* ChromotingInstance::GetStats() {
   if (!video_renderer_.get())
     return NULL;