Refactor OS_LINUX preprocessor directive for LaCrOS effort.

Currently, ChromeOS defines the OS_LINUX directive as well as
OS_CHROMEOS.  We're working to separate these two, so we're
making the fact that OS_LINUX == OS_LINUX || OS_CHROMEOS
explicit.

This is changes for /gpu/command_buffer

This CL was uploaded by git cl split.

R=zmo@chromium.org

Bug: 1110266
Change-Id: I360f6a48e084e8e670f80ac6407fac1457eb184b
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2371296
Auto-Submit: Sean McAllister <smcallis@google.com>
Reviewed-by: Zhenyao Mo <zmo@chromium.org>
Commit-Queue: Zhenyao Mo <zmo@chromium.org>
Cr-Commit-Position: refs/heads/master@{#800884}

gpu/command_buffer/service/external_semaphore.cc

@@ -39,7 +39,7 @@ GLuint ImportSemaphoreHandleToGLSemaphore(SemaphoreHandle handle) {
       },
       base::Time::Now()));
 
-#if defined(OS_LINUX) || defined(OS_ANDROID)
+#if defined(OS_LINUX) || defined(OS_CHROMEOS) || defined(OS_ANDROID)
   if (handle.vk_handle_type() !=
       VK_EXTERNAL_SEMAPHORE_HANDLE_TYPE_OPAQUE_FD_BIT) {
     DLOG(ERROR) << "Importing semaphore handle of unexpected type:"

gpu/command_buffer/service/external_vk_image_backing.cc

@@ -29,7 +29,7 @@
 #include "ui/gl/gl_version_info.h"
 #include "ui/gl/scoped_binders.h"
 
-#if defined(OS_LINUX) && BUILDFLAG(USE_DAWN)
+#if (defined(OS_LINUX) || defined(OS_CHROMEOS)) && BUILDFLAG(USE_DAWN)
 #include "gpu/command_buffer/service/external_vk_image_dawn_representation.h"
 #endif
 
@@ -582,7 +582,7 @@ std::unique_ptr<SharedImageRepresentationDawn>
 ExternalVkImageBacking::ProduceDawn(SharedImageManager* manager,
                                     MemoryTypeTracker* tracker,
                                     WGPUDevice wgpuDevice) {
-#if defined(OS_LINUX) && BUILDFLAG(USE_DAWN)
+#if (defined(OS_LINUX) || defined(OS_CHROMEOS)) && BUILDFLAG(USE_DAWN)
   auto wgpu_format = viz::ToWGPUFormat(format());
 
   if (wgpu_format == WGPUTextureFormat_Undefined) {
@@ -601,7 +601,7 @@ ExternalVkImageBacking::ProduceDawn(SharedImageManager* manager,
 
   return std::make_unique<ExternalVkImageDawnRepresentation>(
       manager, this, tracker, wgpuDevice, wgpu_format, std::move(memory_fd));
-#else  // !defined(OS_LINUX) || !BUILDFLAG(USE_DAWN)
+#else  // (!defined(OS_LINUX) && !defined(OS_CHROMEOS)) || !BUILDFLAG(USE_DAWN)
   NOTIMPLEMENTED_LOG_ONCE();
   return nullptr;
 #endif
@@ -614,7 +614,7 @@ GLuint ExternalVkImageBacking::ProduceGLTextureInternal() {
   gl::GLApi* api = gl::g_current_gl_context;
   base::Optional<ScopedDedicatedMemoryObject> memory_object;
   if (!use_separate_gl_texture()) {
-#if defined(OS_LINUX) || defined(OS_ANDROID)
+#if defined(OS_LINUX) || defined(OS_CHROMEOS) || defined(OS_ANDROID)
     auto memory_fd = image_->GetMemoryFd();
     if (!memory_fd.is_valid())
       return 0;

gpu/command_buffer/tests/gl_copy_texture_CHROMIUM_unittest.cc

@@ -258,7 +258,7 @@ void getExpectedColorAndMask(GLenum src_internal_format,
 
       setColor(adjusted_color[0], adjusted_color[1], adjusted_color[2],
                alpha_value, expected_color);
-#if defined(OS_MAC) || defined(OS_LINUX)
+#if defined(OS_MAC) || defined(OS_LINUX) || defined(OS_CHROMEOS)
       // The alpha channel values for LUMINANCE_ALPHA source don't work OK
       // on Mac or Linux, so skip comparison of those, see crbug.com/926579
       setColor(1, 1, 1, src_internal_format != GL_LUMINANCE_ALPHA,
@@ -643,7 +643,8 @@ class GLCopyTextureCHROMIUMES3Test : public GLCopyTextureCHROMIUMTest {
 
   bool ShouldSkipNorm16() const {
     DCHECK(!ShouldSkipTest());
-#if (defined(OS_MAC) || defined(OS_WIN) || defined(OS_LINUX)) && \
+#if (defined(OS_MAC) || defined(OS_WIN) || defined(OS_LINUX) || \
+     defined(OS_CHROMEOS)) &&                                   \
     (defined(ARCH_CPU_X86) || defined(ARCH_CPU_X86_64))
     // Make sure it's tested; it is safe to assume that the flag is always true
     // on desktop.
@@ -655,7 +656,7 @@ class GLCopyTextureCHROMIUMES3Test : public GLCopyTextureCHROMIUMTest {
 
   bool ShouldSkipRGBA16ToRGB10A2() const {
     DCHECK(!ShouldSkipTest());
-#if (defined(OS_MAC) || defined(OS_LINUX)) && \
+#if (defined(OS_MAC) || defined(OS_LINUX) || defined(OS_CHROMEOS)) && \
     (defined(ARCH_CPU_X86) || defined(ARCH_CPU_X86_64))
     // // TODO(crbug.com/1046873): Fails on mac and linux intel.
     return true;