content: Implement dynamic priorities for raster threads.

base/threading/platform_thread_posix.cc

Index: base/threading/platform_thread_posix.cc
diff --git a/base/threading/platform_thread_posix.cc b/base/threading/platform_thread_posix.cc
index bd6ae2dc09913b6396469455f16891dba90948a8..fa7ba3b36922874d11e8e27b46ae41313037f88b 100644
--- a/base/threading/platform_thread_posix.cc
+++ b/base/threading/platform_thread_posix.cc
@@ -259,6 +259,15 @@ ThreadPriority PlatformThread::GetCurrentThreadPriority() {
 #endif  // !defined(OS_NACL)
 }
 
+// static
+bool PlatformThread::SetChildThreadPriorityInCurrentProcess(
+    PlatformThreadHandle thread_handle,
+    PlatformThreadId tid,
+    ThreadPriority priority) {
+  // FIXME: Add check for caller process and thread's process.
+  return internal::SetChildThreadPriorityInCurrentProcess(tid, priority);
+}
+
 #endif  // !defined(OS_MACOSX)
 
 }  // namespace base