Revert "Don't create manager objects in ContextGroup when using the passthrough decoder"

This reverts commit 248bfd1f.

Reason for revert: Broke some Android WebGL video tests

BUG=1047201

Original change's description:
> Don't create manager objects in ContextGroup when using the passthrough decoder
> 
> These objects are not used when the passthrough command decoder is in
> use.  This saves several GPU memory allocations in TextureManager for
> default and black textures.
> 
> Saves ~2 MB per context.
> 
> BUG=1046613
> BUG=1030835
> 
> Change-Id: I66c6acf28580742bc313d8cf79de80f7f7d98305
> Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2028291
> Commit-Queue: Geoff Lang <geofflang@chromium.org>
> Reviewed-by: Zhenyao Mo <zmo@chromium.org>
> Reviewed-by: Dan Sanders <sandersd@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#736631}

TBR=zmo@chromium.org,geofflang@chromium.org,sandersd@chromium.org

Change-Id: I82ca36bd0b449e743ef819fbfe6ad161b219a8d0
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: 1046613, 1030835
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2031164Reviewed-by: Geoff Lang <geofflang@chromium.org>
Commit-Queue: Geoff Lang <geofflang@chromium.org>
Cr-Commit-Position: refs/heads/master@{#736863}

gpu/command_buffer/service/context_group.cc

@@ -263,9 +263,6 @@ gpu::ContextResult ContextGroup::Initialize(
                 &uniform_buffer_offset_alignment_);
   }
 
-  // Managers are not used by the passthrough command decoder. Save memory by
-  // not allocating them.
-  if (!use_passthrough_cmd_decoder_) {
   buffer_manager_ = std::make_unique<BufferManager>(memory_tracker_.get(),
                                                     feature_info_.get());
   renderbuffer_manager_ = std::make_unique<RenderbufferManager>(
@@ -273,7 +270,6 @@ gpu::ContextResult ContextGroup::Initialize(
       feature_info_.get());
   shader_manager_ = std::make_unique<ShaderManager>(progress_reporter_);
   sampler_manager_ = std::make_unique<SamplerManager>(feature_info_.get());
-  }
 
   // Lookup GL things we need to know.
   const GLint kGLES2RequiredMinimumVertexAttribs = 8u;
@@ -393,15 +389,11 @@ gpu::ContextResult ContextGroup::Initialize(
                  feature_info_->workarounds().max_3d_array_texture_size);
   }
 
-  // Managers are not used by the passthrough command decoder. Save memory by
-  // not allocating them.
-  if (!use_passthrough_cmd_decoder_) {
   texture_manager_.reset(new TextureManager(
       memory_tracker_.get(), feature_info_.get(), max_texture_size,
       max_cube_map_texture_size, max_rectangle_texture_size,
       max_3d_texture_size, max_array_texture_layers, bind_generates_resource_,
       progress_reporter_, discardable_manager_));
-  }
 
   const GLint kMinTextureImageUnits = 8;
   const GLint kMinVertexTextureImageUnits = 0;
@@ -531,9 +523,6 @@ gpu::ContextResult ContextGroup::Initialize(
     }
   }
 
-  // Managers are not used by the passthrough command decoder. Save memory by
-  // not allocating them.
-  if (!use_passthrough_cmd_decoder_) {
   path_manager_ = std::make_unique<PathManager>();
 
   program_manager_ = std::make_unique<ProgramManager>(
@@ -542,7 +531,6 @@ gpu::ContextResult ContextGroup::Initialize(
       feature_info_.get(), progress_reporter_);
 
   texture_manager_->Initialize();
-  }
 
   decoders_.push_back(decoder->AsWeakPtr());
   return gpu::ContextResult::kSuccess;

media/gpu/command_buffer_helper.cc

@@ -15,6 +15,7 @@
 #include "gpu/command_buffer/service/decoder_context.h"
 #include "gpu/command_buffer/service/scheduler.h"
 #include "gpu/command_buffer/service/sync_point_manager.h"
+#include "gpu/command_buffer/service/texture_manager.h"
 #include "gpu/ipc/service/command_buffer_stub.h"
 #include "gpu/ipc/service/gpu_channel.h"
 #include "media/gpu/gles2_decoder_helper.h"

media/gpu/gles2_decoder_helper.cc

@@ -14,6 +14,7 @@
 #include "gpu/command_buffer/service/context_group.h"
 #include "gpu/command_buffer/service/decoder_context.h"
 #include "gpu/command_buffer/service/mailbox_manager.h"
+#include "gpu/command_buffer/service/texture_manager.h"
 #include "ui/gl/gl_context.h"
 #include "ui/gl/scoped_binders.h"
 
@@ -27,7 +28,10 @@ class GLES2DecoderHelperImpl : public GLES2DecoderHelper {
       : decoder_(decoder) {
     DCHECK(decoder_);
     gpu::gles2::ContextGroup* group = decoder_->GetContextGroup();
+    texture_manager_ = group->texture_manager();
     mailbox_manager_ = group->mailbox_manager();
+    // TODO(sandersd): Support GLES2DecoderPassthroughImpl.
+    DCHECK(texture_manager_);
     DCHECK(mailbox_manager_);
   }
 
@@ -93,6 +97,7 @@ class GLES2DecoderHelperImpl : public GLES2DecoderHelper {
 
  private:
   gpu::DecoderContext* decoder_;
+  gpu::gles2::TextureManager* texture_manager_;
   gpu::MailboxManager* mailbox_manager_;
   THREAD_CHECKER(thread_checker_);