[Sync] Refactoring of sync integration test checkers to remove boilerplate await methods.

chrome/browser/sync/test/integration/status_change_checker.h

Index: chrome/browser/sync/test/integration/status_change_checker.h
diff --git a/chrome/browser/sync/test/integration/status_change_checker.h b/chrome/browser/sync/test/integration/status_change_checker.h
index b1611cc86b39881da881f2b63ecfe66235879ded..9d62bb091b3dda49df5153b037ceddd7f0ecdd5b 100644
--- a/chrome/browser/sync/test/integration/status_change_checker.h
+++ b/chrome/browser/sync/test/integration/status_change_checker.h
@@ -21,18 +21,25 @@ class ProfileSyncServiceHarness;
 // sense to call StartBlockingWait() more than once.
 class StatusChangeChecker {
  public:
-  explicit StatusChangeChecker();
+  StatusChangeChecker();
 
   // Returns a string representing this current StatusChangeChecker, and
   // possibly some small part of its state.  For example: "AwaitPassphraseError"
   // or "AwaitMigrationDone(BOOKMARKS)".
   virtual std::string GetDebugMessage() const = 0;
 
+  // Returns a bool representing if the state the checker is currently in its

[maxbogue, 2016/09/30 16:27:56]

"Returns whether the state the checker is currently in is its desired
configuration."

Also it's such a descriptive function name you barely need a comment :o

[skym, 2016/09/30 17:43:21]

Right? I was trying really hard to not just repeat the words the method name was
made of!

Also, Done.

+  // desired configuration.
+  virtual bool IsExitConditionSatisfied() = 0;
+
+  // Block if IsExitConditionSatisfied() is currently false until TimeOut()

[maxbogue, 2016/09/30 16:27:56]

"TimedOut()"

Also this makes it sound like you check IsExitConditionSatisfied once and then
wait for TimedOut after that. Maybe clarify that CheckExitCondition can cause
this to exit before TimedOut?

[skym, 2016/09/30 17:43:22]

Done.

+  // becomes true. Checkers should call CheckExitCondition upon changes. Returns
+  // true if IsExitConditionSatisfied() is ultimately true, otherwise false.
+  bool Wait();
+
   // Returns true if the blocking wait was exited because of a timeout.
   bool TimedOut() const;
 
-  virtual bool IsExitConditionSatisfied() = 0;
-
  protected:
   virtual ~StatusChangeChecker();