texture mipmap level is not zero-only in ES 3

gpu/command_buffer/service/texture_manager.cc

Index: gpu/command_buffer/service/texture_manager.cc
diff --git a/gpu/command_buffer/service/texture_manager.cc b/gpu/command_buffer/service/texture_manager.cc
index c7150ee98eee936d0c174cd9246505cbc691eefe..fd6301b9b0fbfd1b283abea5d6a9597d8f679ea2 100644
--- a/gpu/command_buffer/service/texture_manager.cc
+++ b/gpu/command_buffer/service/texture_manager.cc
@@ -1436,6 +1436,8 @@ scoped_refptr<TextureRef>
 
 bool TextureManager::ValidForTarget(
     GLenum target, GLint level, GLsizei width, GLsizei height, GLsizei depth) {
+  if (level > 0 && !feature_info_->IsES3Capable())

[Zhenyao Mo, 2015/07/21 21:25:05]

This is the wrong place for this validation.  We only want to validate level ==
0 in ES2 for glFramebufferTexture2D/Multisample, but ValidForTarget is for
TexImage2D() etc.  So basically you limit level to 0 for all texture related
operations.

The validation should go to GLES2DecoderImpl::DoFramebufferTexture2D().

Also, you should use IsES3Enabled(), not IsES3Capable().  We could still run ES2
context on top of ES3 drivers.

+    return false;
   GLsizei max_size = MaxSizeForTarget(target) >> level;
   return level >= 0 &&
          width >= 0 &&