Add Resume logic of Purge+Suspend to TabManager.

chrome/browser/memory/tab_manager_web_contents_data.cc

Index: chrome/browser/memory/tab_manager_web_contents_data.cc
diff --git a/chrome/browser/memory/tab_manager_web_contents_data.cc b/chrome/browser/memory/tab_manager_web_contents_data.cc
index 497788accfca4fc6e848fc7cf875d55d63bb74b4..92ebc887cf0a8566ac907b3f32d449f356dc62d6 100644
--- a/chrome/browser/memory/tab_manager_web_contents_data.cc
+++ b/chrome/browser/memory/tab_manager_web_contents_data.cc
@@ -204,7 +204,7 @@ bool TabManager::WebContentsData::IsAutoDiscardable() {
 
 void TabManager::WebContentsData::SetPurgeAndSuspendState(
     PurgeAndSuspendState state) {
-  last_purge_and_suspend_modified_time_ = TimeTicks::Now();
+  last_purge_and_suspend_modified_time_ = NowTicks();
   purge_and_suspend_state_ = state;
 }
 
@@ -213,6 +213,11 @@ base::TimeTicks TabManager::WebContentsData::LastPurgeAndSuspendModifiedTime()
   return last_purge_and_suspend_modified_time_;
 }
 
+void TabManager::WebContentsData::SetLastPurgeAndSuspendModifiedTimeForTesting(
+    base::TimeTicks timestamp) {
+  last_purge_and_suspend_modified_time_ = timestamp;
+}
+
 TabManager::PurgeAndSuspendState
 TabManager::WebContentsData::GetPurgeAndSuspendState() const {
   return purge_and_suspend_state_;