[Fuchsia] Disable fallback to SW compositing.

Previously WebEngine was falling back to SW compositing after 3
GPU process crashes. This is not desirable when Vulkan is enabled
because it may mask other issues. Also not all features work correctly
with SW compositing (e.g. it's not compatible with HW video decoder).

Also added --disable-software-rasterizer to disable SwiftShader as
we should never need to use it on Fuchsia.

Bug: 1021844
Change-Id: I3257d9f0372789849a2922b514e6b23e08a380e0
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1854893
Commit-Queue: Sergey Ulanov <sergeyu@chromium.org>
Reviewed-by: Sergey Ulanov <sergeyu@chromium.org>
Reviewed-by: Wez <wez@chromium.org>
Reviewed-by: Jonathan Backer <backer@chromium.org>
Cr-Commit-Position: refs/heads/master@{#713063}

content/browser/gpu/gpu_data_manager_impl_private.cc

@@ -966,10 +966,12 @@ gpu::GpuMode GpuDataManagerImplPrivate::GetGpuMode() const {
 }
 
 void GpuDataManagerImplPrivate::FallBackToNextGpuMode() {
-#if defined(OS_ANDROID) || defined(OS_CHROMEOS)
+#if defined(OS_ANDROID) || defined(OS_CHROMEOS) || defined(OS_FUCHSIA)
   // Android and Chrome OS can't switch to software compositing. If the GPU
   // process initialization fails or GPU process is too unstable then crash the
   // browser process to reset everything.
+  // On Fuchsia Vulkan must be used when it's enabled by the WebEngine embedder.
+  // Falling back to SW compositing in that case is not supported.
 #if defined(OS_ANDROID)
   FatalGpuProcessLaunchFailureOnBackground();
 #endif

fuchsia/engine/context_provider_impl.cc

@@ -247,14 +247,20 @@ void ContextProviderImpl::Create(
   }
 
   if (enable_vulkan) {
+    DLOG(ERROR) << "Enabling Vulkan GPU acceleration.";
     launch_command.AppendSwitch(switches::kUseVulkan);
     launch_command.AppendSwitchASCII(switches::kEnableFeatures,
                                      features::kUseSkiaRenderer.name);
     launch_command.AppendSwitch(switches::kEnableOopRasterization);
+    launch_command.AppendSwitch(switches::kDisableSoftwareRasterizer);
     launch_command.AppendSwitchASCII(switches::kUseGL,
                                      gl::kGLImplementationStubName);
     launch_command.AppendSwitchASCII(switches::kGrContextType,
                                      switches::kGrContextTypeVulkan);
+  } else {
+    DLOG(ERROR) << "Disabling GPU acceleration.";
+    launch_command.AppendSwitch(switches::kDisableGpu);
+    launch_command.AppendSwitch(switches::kDisableSoftwareRasterizer);
   }
 
   if (enable_widevine) {

fuchsia/runners/BUILD.gn

@@ -28,6 +28,20 @@ buildflag_header("buildflags") {
   visibility = [ ":*" ]
 }
 
+# TODO(https://crbug.com/1021844): Remove this hack once we have Vulkan
+# emulation available via AEMU.
+source_set("detect_vulkan_hack") {
+  sources = [
+    "common/detect_vulkan_hack.cc",
+    "common/detect_vulkan_hack.h",
+  ]
+  deps = [
+    "//gpu/vulkan",
+    "//third_party/fuchsia-sdk/sdk:web",
+  ]
+  visibility = [ ":*" ]
+}
+
 # Files common to both cast_runner and web_runner targets.
 source_set("common") {
   sources = [
@@ -92,6 +106,7 @@ executable("cast_runner_exe") {
     ":buildflags",
     ":cast_runner_core",
     ":common",
+    ":detect_vulkan_hack",
     "//base",
     "//fuchsia/base",
   ]
@@ -206,6 +221,7 @@ executable("web_runner_exe") {
   ]
   deps = [
     ":common",
+    ":detect_vulkan_hack",
     "//base",
     "//fuchsia/base",
   ]

fuchsia/runners/cast/main.cc

@@ -13,6 +13,7 @@
 #include "fuchsia/base/init_logging.h"
 #include "fuchsia/runners/buildflags.h"
 #include "fuchsia/runners/cast/cast_runner.h"
+#include "fuchsia/runners/common/detect_vulkan_hack.h"
 
 int main(int argc, char** argv) {
   base::SingleThreadTaskExecutor io_task_executor(base::MessagePumpType::IO);
@@ -31,6 +32,9 @@ int main(int argc, char** argv) {
       fuchsia::web::ContextFeatureFlags::HARDWARE_VIDEO_DECODER |
       fuchsia::web::ContextFeatureFlags::WIDEVINE_CDM;
 
+  // Vulkan is not currently available in our integration test environment.
+  DisableVulkanIfUnavailable(&features);
+
   if (!BUILDFLAG(ENABLE_SOFTWARE_VIDEO_DECODERS))
     features |= fuchsia::web::ContextFeatureFlags::HARDWARE_VIDEO_DECODER_ONLY;
 

fuchsia/runners/common/DEPS

+include_rules = [
+  "+gpu/vulkan",
+]

fuchsia/runners/common/detect_vulkan_hack.cc

+// Copyright 2019 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "fuchsia/runners/common/detect_vulkan_hack.h"
+#include "gpu/vulkan/vulkan_function_pointers.h"
+
+// Removes the VULKAN feature flag if Vulkan is not available on the host.
+void DisableVulkanIfUnavailable(fuchsia::web::ContextFeatureFlags* features) {
+  gpu::VulkanFunctionPointers* vulkan_ptrs = gpu::GetVulkanFunctionPointers();
+  if (!vulkan_ptrs->BindUnassociatedFunctionPointers())
+    *features &= ~fuchsia::web::ContextFeatureFlags::VULKAN;
+}

fuchsia/runners/common/detect_vulkan_hack.h

+// Copyright 2019 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef FUCHSIA_RUNNERS_COMMON_DETECT_VULKAN_HACK_H_
+#define FUCHSIA_RUNNERS_COMMON_DETECT_VULKAN_HACK_H_
+
+#include <fuchsia/web/cpp/fidl.h>
+
+// Removes the VULKAN feature flag if Vulkan is not available on the host.
+// TODO(https://crbug.com/1021844): Remove this workaround once our test
+// environment provides Vulkan.
+void DisableVulkanIfUnavailable(fuchsia::web::ContextFeatureFlags* features);
+
+#endif  // FUCHSIA_RUNNERS_COMMON_DETECT_VULKAN_HACK_H_

fuchsia/runners/web/main.cc

@@ -10,6 +10,7 @@
 #include "base/run_loop.h"
 #include "base/task/single_thread_task_executor.h"
 #include "fuchsia/base/init_logging.h"
+#include "fuchsia/runners/common/detect_vulkan_hack.h"
 #include "fuchsia/runners/common/web_content_runner.h"
 
 int main(int argc, char** argv) {
@@ -22,17 +23,19 @@ int main(int argc, char** argv) {
     return 1;
   }
 
-  constexpr fuchsia::web::ContextFeatureFlags kWebRunnerFeatures =
+  fuchsia::web::ContextFeatureFlags features =
       fuchsia::web::ContextFeatureFlags::NETWORK |
       fuchsia::web::ContextFeatureFlags::AUDIO |
       fuchsia::web::ContextFeatureFlags::VULKAN |
       fuchsia::web::ContextFeatureFlags::HARDWARE_VIDEO_DECODER |
       fuchsia::web::ContextFeatureFlags::WIDEVINE_CDM;
 
+  // Vulkan is not currently available in our integration test environment.
+  DisableVulkanIfUnavailable(&features);
+
   WebContentRunner runner(
       base::fuchsia::ComponentContextForCurrentProcess()->outgoing().get(),
-      base::BindOnce(&WebContentRunner::CreateDefaultWebContext,
-                     kWebRunnerFeatures));
+      base::BindOnce(&WebContentRunner::CreateDefaultWebContext, features));
 
   base::fuchsia::ComponentContextForCurrentProcess()
       ->outgoing()