Hide the cursor on the client when it is hidden on the host

remoting/protocol/client_control_dispatcher.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "remoting/protocol/client_control_dispatcher.h"
 
 #include "base/bind_helpers.h"
 #include "base/callback.h"
 #include "base/callback_helpers.h"
 #include "base/message_loop/message_loop_proxy.h"
@@ skipping 20 matching lines @@
       !cursor_shape.has_hotspot_y()) {
     LOG(ERROR) << "Cursor shape is missing required fields.";
     return false;
   }
 
   int width = cursor_shape.width();
   int height = cursor_shape.height();
 
   // Verify that |width| and |height| are within sane limits. Otherwise integer
   // overflow can occur while calculating |cursor_total_bytes| below.
-  if (width <= 0 || width > (SHRT_MAX / 2) ||
-      height <= 0 || height > (SHRT_MAX / 2)) {
+  if (width < 0 || width > (SHRT_MAX / 2) ||
+      height < 0 || height > (SHRT_MAX / 2)) {

[Wez, 2015/01/06 23:24:25]

Since you're making this change in the client-side control channel dispatcher,
it won't "go live" until either we switch over entirely to the v2 app, or this
change makes it into Chrome.

Are we already hitting this when other hosts see empty cursors?

     LOG(ERROR) << "Cursor dimensions are out of bounds for SetCursor: "
                << width << "x" << height;
     return false;
   }
 
   uint32 cursor_total_bytes = width * height * kBytesPerPixel;
   if (cursor_shape.data().size() < cursor_total_bytes) {
     LOG(ERROR) << "Expected " << cursor_total_bytes << " bytes for a "
                << width << "x" << height << " cursor. Only received "
                << cursor_shape.data().size() << " bytes";
@@ skipping 86 matching lines @@
     client_stub_->SetPairingResponse(message->pairing_response());
   } else if (message->has_extension_message()) {
     client_stub_->DeliverHostMessage(message->extension_message());
   } else {
     LOG(WARNING) << "Unknown control message received.";
   }
 }
 
 }  // namespace protocol
 }  // namespace remoting