Add TransformFeedback related APIs to command buffer: PART I.

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 3243cd950eb6a488f987a2c11d73883ac25e61af..88b9c72fa013bdfd4efc23739211c68eb90d8aa0 100644
--- a/gpu/command_buffer/client/gles2_implementation.cc
+++ b/gpu/command_buffer/client/gles2_implementation.cc
@@ -2318,6 +2318,10 @@ void GLES2Implementation::GenSamplersHelper(
     GLsizei /* n */, const GLuint* /* samplers */) {
 }
 
+void GLES2Implementation::GenTransformFeedbacksHelper(
+    GLsizei /* n */, const GLuint* /* transformfeedbacks */) {
+}
+
 // NOTE #1: On old versions of OpenGL, calling glBindXXX with an unused id
 // generates a new resource. On newer versions of OpenGL they don't. The code
 // related to binding below will need to change if we switch to the new OpenGL
@@ -2704,6 +2708,23 @@ void GLES2Implementation::DeleteSamplersHelper(
   }
 }
 
+void GLES2Implementation::DeleteTransformFeedbacksStub(
+    GLsizei n, const GLuint* transformfeedbacks) {
+  helper_->DeleteTransformFeedbacksImmediate(n, transformfeedbacks);
+}
+
+void GLES2Implementation::DeleteTransformFeedbacksHelper(
+    GLsizei n, const GLuint* transformfeedbacks) {
+  if (!GetIdHandler(id_namespaces::kTransformFeedbacks)->FreeIds(
+      this, n, transformfeedbacks,
+      &GLES2Implementation::DeleteTransformFeedbacksStub)) {
+    SetGLError(
+        GL_INVALID_VALUE,
+        "glDeleteTransformFeedbacks", "id not created by this context.");
+    return;
+  }
+}
+
 void GLES2Implementation::DeleteValuebuffersCHROMIUMStub(
     GLsizei n,
     const GLuint* valuebuffers) {