Rename ClientDimensions to ClientResolution and add pixel-size and DPI fields.

remoting/proto/internal.proto

Index: remoting/proto/internal.proto
diff --git a/remoting/proto/internal.proto b/remoting/proto/internal.proto
index 7f06f9d91d700cb10d7999bf9d105ec8b0a56a0d..21f32da340e00ae4d71540a8fafd6a378165f4c8 100644
--- a/remoting/proto/internal.proto
+++ b/remoting/proto/internal.proto
@@ -17,7 +17,7 @@ package remoting.protocol;
 // Represents a message being sent on the control channel.
 message ControlMessage {
   optional ClipboardEvent clipboard_event = 1;
-  optional ClientDimensions client_dimensions = 2;
+  optional ClientResolution client_resolution = 2;
   optional CursorShapeInfo cursor_shape = 4;
   optional VideoControl video_control = 3;
   optional AudioControl audio_control = 5;