Revert of Convert network hints to Mojo

chrome/renderer/chrome_content_renderer_client.cc

Index: chrome/renderer/chrome_content_renderer_client.cc
diff --git a/chrome/renderer/chrome_content_renderer_client.cc b/chrome/renderer/chrome_content_renderer_client.cc
index b51488ec6c19ba172bb98b24738e132b4b204f10..6b808741731215381389a0bf31629d8e69e7061c 100644
--- a/chrome/renderer/chrome_content_renderer_client.cc
+++ b/chrome/renderer/chrome_content_renderer_client.cc
@@ -342,6 +342,8 @@
   ChromeExtensionsRendererClient::GetInstance()->RenderThreadStarted();
 #endif
 
+  prescient_networking_dispatcher_.reset(
+      new network_hints::PrescientNetworkingDispatcher());
 #if defined(ENABLE_SPELLCHECK)
   // ChromeRenderViewTest::SetUp() creates a Spellcheck and injects it using
   // SetSpellcheck(). Don't overwrite it.
@@ -1138,7 +1140,7 @@
 
 blink::WebPrescientNetworking*
 ChromeContentRendererClient::GetPrescientNetworking() {
-  return chrome_observer_->prescient_networking_dispatcher();
+  return prescient_networking_dispatcher_.get();
 }
 
 bool ChromeContentRendererClient::ShouldOverridePageVisibilityState(