Add generated and hand-written passthrough command handlers with stub Doers.

gpu/command_buffer/service/gles2_cmd_decoder_passthrough.cc

Index: gpu/command_buffer/service/gles2_cmd_decoder_passthrough.cc
diff --git a/gpu/command_buffer/service/gles2_cmd_decoder_passthrough.cc b/gpu/command_buffer/service/gles2_cmd_decoder_passthrough.cc
index c9c6b8fc91189351b5113458a41d836edc237653..3b334907c30a8918ef796a257e0d521dc41a403a 100644
--- a/gpu/command_buffer/service/gles2_cmd_decoder_passthrough.cc
+++ b/gpu/command_buffer/service/gles2_cmd_decoder_passthrough.cc
@@ -343,6 +343,12 @@ class GLES2DecoderPassthroughImpl : public GLES2Decoder {
   DebugMarkerManager debug_marker_manager_;
   Logger logger_;
 
+#define GLES2_CMD_OP(name) \
+  Error Handle##name(uint32_t immediate_data_size, const void* data);
+
+  GLES2_COMMAND_LIST(GLES2_CMD_OP)
+#undef GLES2_CMD_OP
+
   using CmdHandler =
       Error (GLES2DecoderPassthroughImpl::*)(uint32_t immediate_data_size,
                                              const void* data);
@@ -368,10 +374,23 @@ class GLES2DecoderPassthroughImpl : public GLES2Decoder {
   // The ContextGroup for this decoder uses to track resources.
   scoped_refptr<ContextGroup> group_;
   scoped_refptr<FeatureInfo> feature_info_;
+
+// Include the prototypes of all the doer functions from a separate header to
+// keep this file clean.
+#include "gpu/command_buffer/service/gles2_cmd_decoder_passthrough_doer_prototypes.h"
 };
 
+#define GLES2_CMD_OP(name)                                               \
+  {                                                                      \
+      &GLES2DecoderPassthroughImpl::Handle##name, cmds::name::kArgFlags, \
+      cmds::name::cmd_flags,                                             \
+      sizeof(cmds::name) / sizeof(CommandBufferEntry) - 1,               \
+  }, /* NOLINT */
+
 const GLES2DecoderPassthroughImpl::CommandInfo
-    GLES2DecoderPassthroughImpl::command_info[] = {};
+    GLES2DecoderPassthroughImpl::command_info[] = {
+        GLES2_COMMAND_LIST(GLES2_CMD_OP)};
+#undef GLES2_CMD_OP
 
 GLES2Decoder* CreateGLES2DecoderPassthroughImpl(ContextGroup* group) {
   return new GLES2DecoderPassthroughImpl(group);
@@ -379,3 +398,6 @@ GLES2Decoder* CreateGLES2DecoderPassthroughImpl(ContextGroup* group) {
 
 }  // namespace gles2
 }  // namespace gpu
+
+#include "gpu/command_buffer/service/gles2_cmd_decoder_passthrough_doers.h"
+#include "gpu/command_buffer/service/gles2_cmd_decoder_passthrough_handlers.h"