USE_X11 and USE_OZONE: //gpu: choose between ozone and x11 path

This patch resolves mostly to the following pattern:

#if defined(USE_X11)
DoThis();
#elif defined(USE_OZONE)
OzonePlatform::DoThat();
#endif

Two ifdefs are combined to a single ifdef now with
if (IsUsingOzonePlatform()) condition is added.

-----

PS: Please note that this is a temp solution that will help to choose
between ozone and non-ozone X11 build. The switch that will be used
to choose the path is --enable-features=UseOzonePlatform. Once
non-Ozone X11 path is removed (hopefully by Q1 2021 depending on how
th finch trial goes), the wrapper will be removed.

Please also note that it's impossible to build use_x11 && use_ozone
without some hacks in PlatformCursor code. The changes to that are
on their way to upstream.

----

Bug: 1085700
Change-Id: Ie8f8560ffb9ab7ab24b10412a5a612c3cc279373
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2250250
Commit-Queue: Maksim Sisov (GMT+3) <msisov@igalia.com>
Reviewed-by: Zhenyao Mo <zmo@chromium.org>
Reviewed-by: Tom Sepez <tsepez@chromium.org>
Cr-Commit-Position: refs/heads/master@{#790369}

gpu/command_buffer/service/BUILD.gn

@@ -324,7 +324,10 @@ target(link_target_type, "gles2_sources") {
   ]
 
   if (use_ozone) {
-    deps += [ "//ui/ozone" ]
+    deps += [
+      "//ui/base:features",
+      "//ui/ozone",
+    ]
   }
 
   if (enable_vulkan) {

gpu/command_buffer/service/gles2_cmd_decoder.cc

@@ -118,6 +118,10 @@
 #include <OpenGL/CGLIOSurface.h>
 #endif  // OS_MACOSX
 
+#if defined(USE_OZONE)
+#include "ui/base/ui_base_features.h"  // nogncheck
+#endif
+
 // Note: this undefs far and near so include this after other Windows headers.
 #include "third_party/angle/src/image_util/loadimage.h"
 
@@ -3216,14 +3220,14 @@ bool BackTexture::AllocateNativeGpuMemoryBuffer(const gfx::Size& size,
   bool is_cleared = false;
   gfx::BufferFormat buffer_format = gfx::BufferFormat::RGBA_8888;
   if (format == GL_RGB) {
+    buffer_format = gfx::BufferFormat::RGBX_8888;
 #if defined(USE_OZONE)
     // BGRX format is preferred for Ozone as it matches the format used by the
     // buffer queue and is as a result guaranteed to work on all devices.
     // TODO(reveman): Define this format in one place instead of having to
     // duplicate BGRX_8888.
-    buffer_format = gfx::BufferFormat::BGRX_8888;
-#else
-    buffer_format = gfx::BufferFormat::RGBX_8888;
+    if (features::IsUsingOzonePlatform())
+      buffer_format = gfx::BufferFormat::BGRX_8888;
 #endif
   }
   scoped_refptr<gl::GLImage> image =

gpu/ipc/common/gpu_memory_buffer_support.cc

@@ -8,6 +8,7 @@
 #include "base/notreached.h"
 #include "build/build_config.h"
 #include "gpu/ipc/common/gpu_memory_buffer_impl_shared_memory.h"
+#include "ui/base/ui_base_features.h"
 #include "ui/gfx/buffer_format_util.h"
 #include "ui/gfx/buffer_usage_util.h"
 
@@ -46,8 +47,12 @@ namespace gpu {
 
 GpuMemoryBufferSupport::GpuMemoryBufferSupport() {
 #if defined(USE_OZONE)
-  client_native_pixmap_factory_ = ui::CreateClientNativePixmapFactoryOzone();
-#elif defined(OS_LINUX)
+  if (features::IsUsingOzonePlatform()) {
+    client_native_pixmap_factory_ = ui::CreateClientNativePixmapFactoryOzone();
+    return;
+  }
+#endif
+#if defined(OS_LINUX)
   client_native_pixmap_factory_.reset(
       gfx::CreateClientNativePixmapFactoryDmabuf());
 #endif
@@ -116,10 +121,13 @@ bool GpuMemoryBufferSupport::IsNativeGpuMemoryBufferConfigurationSupported(
   }
   NOTREACHED();
   return false;
-#elif defined(USE_OZONE)
-  return ui::OzonePlatform::GetInstance()->IsNativePixmapConfigSupported(format,
-                                                                         usage);
-#elif defined(USE_X11)
+#elif defined(USE_OZONE) || defined(USE_X11)
+#if defined(USE_OZONE)
+  if (features::IsUsingOzonePlatform()) {
+    return ui::OzonePlatform::GetInstance()->IsNativePixmapConfigSupported(
+        format, usage);
+  }
+#endif
   // On X11, GPU memory buffer support can only be determined after GPU
   // initialization.
   // viz::HostGpuMemoryBufferManager::IsNativeGpuMemoryBufferConfiguration()

gpu/vulkan/BUILD.gn

@@ -165,6 +165,7 @@ if (enable_vulkan) {
     sources = [ "tests/native_window.h" ]
 
     deps = [
+      "//ui/base:features",
       "//ui/gfx",
       "//ui/gfx:native_widget_types",
     ]

gpu/vulkan/tests/native_window.cc

@@ -5,6 +5,7 @@
 #include "gpu/vulkan/tests/native_window.h"
 
 #include "base/containers/flat_map.h"
+#include "ui/base/ui_base_features.h"
 #include "ui/platform_window/platform_window_delegate.h"
 #include "ui/platform_window/platform_window_init_properties.h"
 
@@ -26,15 +27,23 @@ class Window : public ui::PlatformWindowDelegate {
 
   void Initialize(const gfx::Rect& bounds) {
     DCHECK(!platform_window_);
-#if defined(USE_OZONE)
-    ui::PlatformWindowInitProperties props(bounds);
-    platform_window_ = ui::OzonePlatform::GetInstance()->CreatePlatformWindow(
-        this, std::move(props));
-#elif defined(USE_X11)
+
+#if defined(USE_OZONE) || defined(USE_X11)
     ui::PlatformWindowInitProperties props(bounds);
-    auto x11_window = std::make_unique<ui::X11Window>(this);
-    x11_window->Initialize(std::move(props));
-    platform_window_ = std::move(x11_window);
+#if defined(USE_OZONE)
+    if (features::IsUsingOzonePlatform()) {
+      platform_window_ = ui::OzonePlatform::GetInstance()->CreatePlatformWindow(
+          this, std::move(props));
+    }
+#endif
+#if defined(USE_X11)
+    if (!platform_window_) {
+      DCHECK(!features::IsUsingOzonePlatform());
+      auto x11_window = std::make_unique<ui::X11Window>(this);
+      x11_window->Initialize(std::move(props));
+      platform_window_ = std::move(x11_window);
+    }
+#endif
 #else
     NOTIMPLEMENTED();
     return;