GLES2Debugger: Make command exchange async to improve performance.

In message loop, use select to check for available commands from client,
 rather than always expecting commands in eglSwapBuffers.

Change-Id: Ifc34dd77c2528c8b9c71f594e3eda4f93400cd2b
Signed-off-by: David Li <davidxli@google.com>
diff --git a/opengl/libs/glesv2dbg.h b/opengl/libs/glesv2dbg.h
index b988eb78..8029dce 100644
--- a/opengl/libs/glesv2dbg.h
+++ b/opengl/libs/glesv2dbg.h
@@ -24,7 +24,7 @@
     DbgContext * CreateDbgContext(const unsigned version, const gl_hooks_t * const hooks);
     void DestroyDbgContext(DbgContext * const dbg);
     
-    void StartDebugServer(); // create and bind socket if haven't already
+    void StartDebugServer(unsigned short port); // create and bind socket if haven't already
     void StopDebugServer(); // close socket if open
     
 }; // namespace android