Implement Platform::getUniqueIdForProcess.

content/child/blink_platform_impl.cc

Index: content/child/blink_platform_impl.cc
diff --git a/content/child/blink_platform_impl.cc b/content/child/blink_platform_impl.cc
index 8c19647b15b705b17b61b48751d4158d3545c578..404a82bd60208ba300657498759015c221ea22b6 100644
--- a/content/child/blink_platform_impl.cc
+++ b/content/child/blink_platform_impl.cc
@@ -30,6 +30,7 @@
 #include "base/time/time.h"
 #include "base/trace_event/memory_allocator_dump_guid.h"
 #include "base/trace_event/memory_dump_manager.h"
+#include "base/trace_event/trace_event.h"
 #include "blink/public/resources/grit/blink_image_resources.h"
 #include "blink/public/resources/grit/blink_resources.h"
 #include "components/mime_util/mime_util.h"
@@ -1304,6 +1305,12 @@ size_t BlinkPlatformImpl::maxDecodedImageBytes() {
 #endif
 }
 
+uint32_t BlinkPlatformImpl::getUniqueIdForProcess() {
+  // TODO(rickyz): Replace this with base::GetUniqueIdForProcess when that's
+  // ready.
+  return base::trace_event::TraceLog::GetInstance()->process_id();
+}
+
 scoped_refptr<base::SingleThreadTaskRunner>
 BlinkPlatformImpl::MainTaskRunnerForCurrentThread() {
   if (main_thread_task_runner_.get() &&