content: Implement dynamic priorities for raster threads.

base/threading/platform_thread_linux.cc

Index: base/threading/platform_thread_linux.cc
diff --git a/base/threading/platform_thread_linux.cc b/base/threading/platform_thread_linux.cc
index 95ed32418ff49bdce1cfc91b846374000f62a4e3..2bd8895073a6730f9b34e8e02971f8754fc58030 100644
--- a/base/threading/platform_thread_linux.cc
+++ b/base/threading/platform_thread_linux.cc
@@ -48,6 +48,12 @@ bool SetCurrentThreadPriorityForPlatform(ThreadPriority priority) {
 #endif
 }
 
+bool SetChildThreadPriorityInCurrentProcess(PlatformThreadId tid,
+                                            ThreadPriority priority) {
+  NOTIMPLEMENTED();
+  return false;
+}
+
 bool GetCurrentThreadPriorityForPlatform(ThreadPriority* priority) {
 #if !defined(OS_NACL)
   int maybe_sched_rr = 0;