Revert "Revert 210138 "Perform glReadPixels with PBOs in the gpu, if PBO...""

gpu/command_buffer/client/gles2_implementation.cc

Index: gpu/command_buffer/client/gles2_implementation.cc
diff --git a/gpu/command_buffer/client/gles2_implementation.cc b/gpu/command_buffer/client/gles2_implementation.cc
index 1bc3f0b39f7fbddfe3ef1c9470ba0dbffd374119..e13a1ecb98c0fba06543815db55fb8abb2936e1b 100644
--- a/gpu/command_buffer/client/gles2_implementation.cc
+++ b/gpu/command_buffer/client/gles2_implementation.cc
@@ -2236,8 +2236,7 @@ void GLES2Implementation::ReadPixels(
     if (buffer && buffer->shm_id() != -1) {
       helper_->ReadPixels(xoffset, yoffset, width, height, format, type,
                           buffer->shm_id(), buffer->shm_offset(),
-                          0, 0);
-      buffer->set_transfer_ready_token(helper_->InsertToken());
+                          0, 0, true);
       CheckGLError();
     }
     return;
@@ -2269,7 +2268,8 @@ void GLES2Implementation::ReadPixels(
     helper_->ReadPixels(
         xoffset, yoffset, width, num_rows, format, type,
         buffer.shm_id(), buffer.offset(),
-        GetResultShmId(), GetResultShmOffset());
+        GetResultShmId(), GetResultShmOffset(),
+        false);
     WaitForCmd();
     if (*result != 0) {
       // when doing a y-flip we have to iterate through top-to-bottom chunks