Revert of Added support for Time Elapsed queries through the command buffer.

gpu/command_buffer/client/query_tracker.cc

Index: gpu/command_buffer/client/query_tracker.cc
diff --git a/gpu/command_buffer/client/query_tracker.cc b/gpu/command_buffer/client/query_tracker.cc
index 37a147878a7561cdb609ea536f4f275482c74955..2f379aa4c5c610ace90b2a824f72db0b698f4283 100644
--- a/gpu/command_buffer/client/query_tracker.cc
+++ b/gpu/command_buffer/client/query_tracker.cc
@@ -174,17 +174,18 @@
         helper->IsContextLost()) {
       switch (target()) {
         case GL_COMMANDS_ISSUED_CHROMIUM:
-          result_ = info_.sync->result;
+          result_ = base::saturated_cast<uint32>(info_.sync->result);
           break;
         case GL_LATENCY_QUERY_CHROMIUM:
           // Disabled DCHECK because of http://crbug.com/419236.
           //DCHECK(info_.sync->result >= client_begin_time_us_);
-          result_ = info_.sync->result - client_begin_time_us_;
+          result_ = base::saturated_cast<uint32>(
+              info_.sync->result - client_begin_time_us_);
           break;
         case GL_ASYNC_PIXEL_UNPACK_COMPLETED_CHROMIUM:
         case GL_ASYNC_PIXEL_PACK_COMPLETED_CHROMIUM:
         default:
-          result_ = info_.sync->result;
+          result_ = static_cast<uint32>(info_.sync->result);
           break;
       }
       state_ = kComplete;
@@ -200,7 +201,7 @@
   return state_ == kComplete;
 }
 
-uint64 QueryTracker::Query::GetResult() const {
+uint32 QueryTracker::Query::GetResult() const {
   DCHECK(state_ == kComplete || state_ == kUninitialized);
   return result_;
 }