Fix build rules for //media/gpu:buffer_validation

- Avoid defining this target outside of Linux or CrOS to avoid compile
  errors on systems where native pixmap GpuMemoryBufferHandles aren't
  supported. While this isn't a problem currently, future CLs are
  stricter about only defining GpuMemoryBufferHandle types on platforms
  where they are used.
- Remove unused compiler configs that suppress warnings for global
  constructors/global destructors. This library has no global
  constructors or destructors.

Bug: 40584691
Change-Id: I8d478633dfa10e3d21e4577a2f2cbdb853f28ffe
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/6373153
Reviewed-by: Andres Calderon Jaramillo <andrescj@chromium.org>
Commit-Queue: Andres Calderon Jaramillo <andrescj@chromium.org>
Auto-Submit: Daniel Cheng <dcheng@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1436074}

media/gpu/BUILD.gn

@@ -440,24 +440,21 @@ source_set("common") {
   }
 }
 
-# The buffer validation functionality is in its own component so that it can be
-# depended on without pulling the entire //media/gpu target.
-component("buffer_validation") {
-  defines = [ "IS_MEDIA_GPU_BUFFER_VALIDATION_IMPL" ]
-  sources = [
-    "buffer_validation.cc",
-    "buffer_validation.h",
-  ]
+if (is_linux || is_chromeos) {
+  # The buffer validation functionality is in its own component so that it can be
+  # depended on without pulling the entire //media/gpu target.
+  component("buffer_validation") {
+    defines = [ "IS_MEDIA_GPU_BUFFER_VALIDATION_IMPL" ]
+    sources = [
+      "buffer_validation.cc",
+      "buffer_validation.h",
+    ]
 
-  configs += [
-    "//build/config/compiler:wexit_time_destructors",
-    "//build/config/compiler:wglobal_constructors",
-  ]
-
-  public_deps = [
-    "//base",
-    "//media",
-  ]
+    public_deps = [
+      "//base",
+      "//media",
+    ]
+  }
 }
 
 source_set("command_buffer_helper") {

media/gpu/buffer_validation.cc

@@ -15,15 +15,12 @@
 #include "ui/gfx/geometry/size.h"
 #include "ui/gfx/gpu_memory_buffer.h"
 
-#if BUILDFLAG(IS_LINUX) || BUILDFLAG(IS_CHROMEOS)
 #include <sys/types.h>
 #include <unistd.h>
-#endif  // BUILDFLAG(IS_LINUX) || BUILDFLAG(IS_CHROMEOS)
 
 namespace media {
 
 bool GetFileSize(const int fd, size_t* size) {
-#if BUILDFLAG(IS_LINUX) || BUILDFLAG(IS_CHROMEOS)
   if (fd < 0) {
     VLOG(1) << "Invalid file descriptor";
     return false;
@@ -49,10 +46,6 @@ bool GetFileSize(const int fd, size_t* size) {
 
   *size = base::checked_cast<size_t>(fd_size);
   return true;
-#else
-  NOTIMPLEMENTED();
-  return false;
-#endif  // BUILDFLAG(IS_LINUX) || BUILDFLAG(IS_CHROMEOS)
 }
 
 bool VerifyGpuMemoryBufferHandle(
@@ -77,7 +70,6 @@ bool VerifyGpuMemoryBufferHandle(
     VLOG(1) << "Unsupported: " << pixel_format;
     return false;
   }
-#if BUILDFLAG(IS_LINUX) || BUILDFLAG(IS_CHROMEOS)
   const size_t num_planes = media::VideoFrame::NumPlanes(pixel_format);
   if (num_planes != gmb_handle.native_pixmap_handle.planes.size() ||
       num_planes == 0) {
@@ -133,10 +125,6 @@ bool VerifyGpuMemoryBufferHandle(
     }
   }
   return true;
-#else
-  NOTIMPLEMENTED();
-  return false;
-#endif  // BUILDFLAG(IS_LINUX) || BUILDFLAG(IS_CHROMEOS)
 }
 
 }  // namespace media