Reset GL state

GLES2DecoderImpl hooks into GLStateRestorer for virtual context
switching. These hooks work even without enabling virtual contexts and
are used in DirectContextProvider::SetGLRendererCopierRequiredState.

GLES2DecoderPassthroughImpl does not have any state restoration hooks.
This CL explicitly sets state used by GLRendererCopier, GLScaler, and
GLI420Converter.

Bug: 1016833
Change-Id: I7ebead5148411677765b3d4635871873b7af0018
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1912907Reviewed-by: kylechar <kylechar@chromium.org>
Commit-Queue: Jonathan Backer <backer@chromium.org>
Cr-Commit-Position: refs/heads/master@{#714733}

components/viz/service/display_embedder/direct_context_provider.cc

@@ -154,11 +154,24 @@ void DirectContextProvider::SetGLRendererCopierRequiredState(
   // SkiaOutputSurfaceImplOnGpu::ScopedUseContextProvider).
   gles2_implementation_->BindFramebuffer(GL_FRAMEBUFFER, 0);
 
-  decoder_->RestoreActiveTexture();
-  decoder_->RestoreProgramBindings();
-  decoder_->RestoreAllAttributes();
-  decoder_->RestoreGlobalState();
-  decoder_->RestoreBufferBindings();
+  auto* group = decoder()->GetContextGroup();
+  if (group->use_passthrough_cmd_decoder()) {
+    // Matches state setting in
+    // SkiaOutputSurfaceImplOnGpu::ScopedUseContextProvider when passthrough
+    // is enabled so that client side and service side state match.
+    //
+    // TODO(backer): Use ANGLE API to force state reset once API is available.
+    gles2_implementation_->UseProgram(0);
+    gles2_implementation_->ActiveTexture(GL_TEXTURE0);
+    gles2_implementation_->BindBuffer(GL_ARRAY_BUFFER, 0);
+    gles2_implementation_->BindTexture(GL_TEXTURE_2D, 0);
+  } else {
+    decoder_->RestoreActiveTexture();
+    decoder_->RestoreProgramBindings();
+    decoder_->RestoreAllAttributes();
+    decoder_->RestoreGlobalState();
+    decoder_->RestoreBufferBindings();
+  }
 
   // At this point |decoder_| cached state (if any, passthrough doesn't cache)
   // is synced with GLContext state. But GLES2Implementation caches some state

components/viz/service/display_embedder/skia_output_surface_impl_on_gpu.cc

@@ -220,6 +220,16 @@ class SkiaOutputSurfaceImplOnGpu::ScopedUseContextProvider {
     // side consistent with that.
     auto* api = impl_on_gpu_->api_;
     api->glBindFramebufferEXTFn(GL_FRAMEBUFFER, 0);
+
+    auto* group = impl_on_gpu->context_provider_->decoder()->GetContextGroup();
+    if (group->use_passthrough_cmd_decoder()) {
+      // Passthrough decoding is not hooked into GLStateRestorer and we must
+      // manually reset the context into a known state after Skia is finished.
+      api->glUseProgramFn(0);
+      api->glActiveTextureFn(GL_TEXTURE0);
+      api->glBindBufferFn(GL_ARRAY_BUFFER, 0);
+      api->glBindTextureFn(GL_TEXTURE_2D, 0);
+    }
     impl_on_gpu_->context_provider_->SetGLRendererCopierRequiredState(
         texture_client_id);
   }