[Sync] Rename SyncEnabledAndLoggedIn() to CanStartSync().

This is part of an effort to clean up sync's state interface.
CanStartSync more accurately represents the conceptual implication of
the conditions that the method checks.

Note that at present, this does not map perfectly to what is actually
checked when sync tries to start, but that will happen in an upcoming
change.

BUG=495192
TBR=sdefresne,pkasting

Review URL: https://codereview.chromium.org/1175243009

Cr-Commit-Position: refs/heads/master@{#334545}
diff --git a/chrome/browser/sync/profile_sync_service_android.cc b/chrome/browser/sync/profile_sync_service_android.cc
index 0e8985e..46b2d7ed 100644
--- a/chrome/browser/sync/profile_sync_service_android.cc
+++ b/chrome/browser/sync/profile_sync_service_android.cc
@@ -176,7 +176,7 @@
   // should start up automatically as long as it has credentials). This can
   // happen normally if (for example) the user closes and reopens the sync
   // settings window quickly during initial startup.
-  if (sync_service_->IsSyncEnabledAndLoggedIn() &&
+  if (sync_service_->CanSyncStart() &&
       sync_service_->IsOAuthRefreshTokenAvailable() &&
       sync_service_->HasSyncSetupCompleted()) {
     return;