Migrate WaitableEvent to enum-based constructor in content/

Change automated with clang-tidy (details @ https://crbug.com/612843#c13)

BUG=612843

Review-Url: https://codereview.chromium.org/2026253003
Cr-Commit-Position: refs/heads/master@{#397386}
diff --git a/content/browser/frame_host/debug_urls.cc b/content/browser/frame_host/debug_urls.cc
index 833b0063..69a61ab0 100644
--- a/content/browser/frame_host/debug_urls.cc
+++ b/content/browser/frame_host/debug_urls.cc
@@ -171,7 +171,9 @@
 
 void HangCurrentThread() {
   ScopedAllowWaitForDebugURL allow_wait;
-  base::WaitableEvent(false, false).Wait();
+  base::WaitableEvent(base::WaitableEvent::ResetPolicy::AUTOMATIC,
+                      base::WaitableEvent::InitialState::NOT_SIGNALED)
+      .Wait();
 }
 
 }  // namespace