gltrace: Trace thread time and wall clock time.

For each gl function, trace both the thread and wall clock
times.

Change-Id: I32b6caa67fa50bf915dab89b3c5021ee82e28d55
diff --git a/opengl/libs/GLES_trace/gltrace.proto b/opengl/libs/GLES_trace/gltrace.proto
index 11cf24f..2893e6e 100644
--- a/opengl/libs/GLES_trace/gltrace.proto
+++ b/opengl/libs/GLES_trace/gltrace.proto
@@ -543,11 +543,13 @@
 
     required int32      context_id = 1;                     // GL context ID
     required int64      start_time = 2;                     // time when call was invoked
-    required int32      duration = 3;                       // duration of the call
+    required int32      duration = 3;                       // duration of the call (MONOTONIC TIME)
 
     required Function   function = 4 [default = invalid];   // GL function called
     repeated DataType   args = 5;                           // GL function's arguments
     optional DataType   returnValue = 6;                    // GL function's return value
 
     optional FrameBuffer fb = 7;                            // contents of the framebuffer
+
+    optional int32      threadtime = 8;                     // duration of the call (THREAD TIME)
 };