gpu: Use a rectangle to keep track of the cleared area of each texture level.

gpu/command_buffer/service/gles2_cmd_decoder_unittest_base.cc

Index: gpu/command_buffer/service/gles2_cmd_decoder_unittest_base.cc
diff --git a/gpu/command_buffer/service/gles2_cmd_decoder_unittest_base.cc b/gpu/command_buffer/service/gles2_cmd_decoder_unittest_base.cc
index 6bd61561fed98bfe09f7aa18a6e6d2b8c84d9b24..8d83fb92765290a452e81eb4d839a5a3ee1de017 100644
--- a/gpu/command_buffer/service/gles2_cmd_decoder_unittest_base.cc
+++ b/gpu/command_buffer/service/gles2_cmd_decoder_unittest_base.cc
@@ -671,8 +671,8 @@ void GLES2DecoderTestBase::SetupClearTextureExpectations(
   EXPECT_CALL(*gl_, BindTexture(bind_target, service_id))
       .Times(1)
       .RetiresOnSaturation();
-  EXPECT_CALL(*gl_, TexImage2D(
-      target, level, internal_format, width, height, 0, format, type, _))
+  EXPECT_CALL(
+      *gl_, TexSubImage2D(target, level, 0, 0, width, height, format, type, _))
       .Times(1)
       .RetiresOnSaturation();
   EXPECT_CALL(*gl_, BindTexture(bind_target, old_service_id))