linux: gles2 client fixes

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 576a1e64725defde906f5540e058e3a9658e6a9e..f79297744a74c2f58bca87351e5ac8c32a98db46 100644
--- a/gpu/command_buffer/client/gles2_implementation.cc
+++ b/gpu/command_buffer/client/gles2_implementation.cc
@@ -17,6 +17,10 @@ static GLuint ToGLuint(const void* ptr) {
   return static_cast<GLuint>(reinterpret_cast<size_t>(ptr));
 }
 
+#if !defined(COMPILER_MSVC)
+const size_t GLES2Implementation::kMaxSizeOfSimpleResult;
+#endif
+
 GLES2Implementation::GLES2Implementation(
       GLES2CmdHelper* helper,
       size_t transfer_buffer_size,