NoState Prefetch: nostate prefetch browser tests.

chrome/browser/prerender/prerender_contents.cc

Index: chrome/browser/prerender/prerender_contents.cc
diff --git a/chrome/browser/prerender/prerender_contents.cc b/chrome/browser/prerender/prerender_contents.cc
index 4ded1cb58613800c9ce874d741aef061fbf84c77..8ea17cb415e7ddc73277335ca000b06204250d30 100644
--- a/chrome/browser/prerender/prerender_contents.cc
+++ b/chrome/browser/prerender/prerender_contents.cc
@@ -186,19 +186,21 @@ class PrerenderContents::WebContentsDelegateImpl
   PrerenderContents* prerender_contents_;
 };
 
+void PrerenderContents::Observer::OnPrerenderStart(
+    PrerenderContents* contents) {}

[pasko, 2016/10/11 13:56:23]

nit: empty bodies would be more readable if they stay in the
prerender_contents.h

[mattcary, 2016/10/11 15:08:58]

I thought we avoided inlining? At any rate, I did this to be consistent with the
existing OnPrerenderStopLoading def.

[pasko, 2016/10/11 15:40:19]

We certainly inline trivial getters, so empty bodies seem natural to inline.

We do both, actually, but your pattern is less common (not sure how much):
shell> git grep 'virtual void.*On.*\(.*\) {}' -- '*.h' | wc -l
553
shell> git grep 'virtual void.*On.*\(.*\);' -- '*.h' | grep -v '= 0' | wc -l
364

I agree that it is good to be consistent here, but the other consistent way to
do it looks more readable/maintainable because:
1. the reader knows that all non-overridden methods are no-ops by just looking
at the interface of this base class
2. less boilerplate-placed-in-correct-namespace to scan through in the .cc file

[mattcary, 2016/10/12 09:02:52]

I like the inlining for empty ftns better myself, done.

+
 void PrerenderContents::Observer::OnPrerenderStopLoading(
-    PrerenderContents* contents) {
-}
+    PrerenderContents* contents) {}
 
 void PrerenderContents::Observer::OnPrerenderDomContentLoaded(
-    PrerenderContents* contents) {
-}
+    PrerenderContents* contents) {}
 
-PrerenderContents::Observer::Observer() {
+void PrerenderContents::Observer::OnPrerenderStop(PrerenderContents* contents) {
 }
 
-PrerenderContents::Observer::~Observer() {
-}
+PrerenderContents::Observer::Observer() {}
+
+PrerenderContents::Observer::~Observer() {}
 
 PrerenderContents::PrerenderContents(
     PrerenderManager* prerender_manager,