Add an IPC method for Blink to call RapporService::RecordSample()

content/browser/user_metrics.cc

Index: content/browser/user_metrics.cc
diff --git a/content/browser/user_metrics.cc b/content/browser/user_metrics.cc
index 200c851ccb170a20d8e51486b7bcd286fc70ec98..853e5e4c8642e5a27095b3393199b9777dfd9912 100644
--- a/content/browser/user_metrics.cc
+++ b/content/browser/user_metrics.cc
@@ -36,4 +36,18 @@ void RecordComputedAction(const std::string& action) {
   base::RecordComputedAction(action);
 }
 
+CONTENT_EXPORT void RecordRappor(
+    const std::string& metric,
+    const std::string& sample) {
+  if (!BrowserThread::CurrentlyOn(BrowserThread::UI)) {
+    BrowserThread::PostTask(
+        BrowserThread::UI,
+        FROM_HERE,
+        base::Bind(&RecordRappor, metric, sample));
+    return;
+  }
+
+  base::RecordRappor(metric, sample);
+}
+
 }  // namespace content