Store URLs in WebappDataStorage, and purge them when history is cleared.

chrome/browser/browsing_data/browsing_data_remover.cc

Index: chrome/browser/browsing_data/browsing_data_remover.cc
diff --git a/chrome/browser/browsing_data/browsing_data_remover.cc b/chrome/browser/browsing_data/browsing_data_remover.cc
index 1fab3eaf2f266882fc8a34409f5144a20b76c0e0..fbbdf85a1f8e0b8ad647d49835fdfb7c41cdc9e4 100644
--- a/chrome/browser/browsing_data/browsing_data_remover.cc
+++ b/chrome/browser/browsing_data/browsing_data_remover.cc
@@ -556,6 +556,13 @@ void BrowsingDataRemover::RemoveImpl(const TimeRange& time_range,
           base::Bind(&BrowsingDataRemover::OnClearedPrecacheHistory,
                      weak_ptr_factory_.GetWeakPtr()));
     }
+
+    // Clear the history information (last launch time and origin URL) of any
+    // registered webapps.
+    waiting_for_clear_webapp_history_ = true;

[gone, 2016/03/08 22:40:39]

The other clearing functions generally seem to PostTaskAndReply; is that not
required in this case because of the AsyncTask in Java land?  If so, it'd be
worth commenting on that here.

[dominickn, 2016/03/09 08:18:33]

I actually have no idea, I was just doing this the same way that the other JNI
call does it. :)

[gone, 2016/03/10 23:27:21]

Ah, in that case could you leave a comment to make it clearer?

[dominickn, 2016/03/11 05:14:42]

Done. The threading model across JNI calls is still evil black magic to me.

+    WebappRegistry::ClearWebappHistory(
+        base::Bind(&BrowsingDataRemover::OnClearedWebappHistory,
+          weak_ptr_factory_.GetWeakPtr()));
 #endif
 
     data_reduction_proxy::DataReductionProxySettings*
@@ -1006,6 +1013,7 @@ bool BrowsingDataRemover::AllDone() {
 #if BUILDFLAG(ANDROID_JAVA_UI)
          !waiting_for_clear_precache_history_ &&
          !waiting_for_clear_webapp_data_ &&
+         !waiting_for_clear_webapp_history_ &&
          !waiting_for_clear_offline_page_data_ &&
 #endif
 #if defined(ENABLE_WEBRTC)
@@ -1198,6 +1206,12 @@ void BrowsingDataRemover::OnClearedWebappData() {
   NotifyIfDone();
 }
 
+void BrowsingDataRemover::OnClearedWebappHistory() {
+  DCHECK_CURRENTLY_ON(BrowserThread::UI);
+  waiting_for_clear_webapp_history_ = false;
+  NotifyIfDone();
+}
+
 void BrowsingDataRemover::OnClearedOfflinePageData() {
   DCHECK_CURRENTLY_ON(BrowserThread::UI);
   waiting_for_clear_offline_page_data_ = false;