Unbind binding_ in oom_intervention_tab_helper

This CL intends to fix a bug where renderer oom detection stops running after reloading / navigation / switching tabs. This was caused because binding_ was never unbound although it was stated as one of the requirements to start detection in renderer.

BUG=829725

Change-Id: I43507a5eb12a6206dca333be4d6d609b1c8fac72
Reviewed-on: https://chromium-review.googlesource.com/999224Reviewed-by: Kenichi Ishibashi <bashi@chromium.org>
Reviewed-by: Kentaro Hara <haraken@chromium.org>
Commit-Queue: Yuzu Saijo <yuzus@chromium.org>
Cr-Commit-Position: refs/heads/master@{#549123}

chrome/browser/android/oom_intervention/oom_intervention_tab_helper.cc

@@ -108,7 +108,7 @@ void OomInterventionTabHelper::AcceptIntervention() {
 
 void OomInterventionTabHelper::DeclineIntervention() {
   RecordInterventionUserDecision(false);
-  intervention_.reset();
+  ResetInterfaces();
   intervention_state_ = InterventionState::DECLINED;
 
   if (decider_) {
@@ -125,7 +125,7 @@ void OomInterventionTabHelper::WebContentsDestroyed() {
 
 void OomInterventionTabHelper::RenderProcessGone(
     base::TerminationStatus status) {
-  intervention_.reset();
+  ResetInterfaces();
 
   // Skip background process termination.
   if (!IsLastVisibleWebContents(web_contents())) {
@@ -167,7 +167,7 @@ void OomInterventionTabHelper::DidStartNavigation(
   if (navigation_handle->IsSameDocument())
     return;
 
-  intervention_.reset();
+  ResetInterfaces();
 
   // Filter out background navigation.
   if (!IsLastVisibleWebContents(navigation_handle->GetWebContents())) {
@@ -259,7 +259,7 @@ void OomInterventionTabHelper::StartMonitoringIfNeeded() {
 
 void OomInterventionTabHelper::StopMonitoring() {
   if (ShouldDetectInRenderer()) {
-    intervention_.reset();
+    ResetInterfaces();
   } else {
     subscription_.reset();
   }
@@ -303,7 +303,7 @@ void OomInterventionTabHelper::OnNearOomDetected() {
 void OomInterventionTabHelper::
     OnDetectionWindowElapsedWithoutHighMemoryUsage() {
   ResetInterventionState();
-  intervention_.reset();
+  ResetInterfaces();
   StartMonitoringIfNeeded();
 }
 
@@ -312,3 +312,9 @@ void OomInterventionTabHelper::ResetInterventionState() {
   intervention_state_ = InterventionState::NOT_TRIGGERED;
   renderer_detection_timer_.AbandonAndStop();
 }
+
+void OomInterventionTabHelper::ResetInterfaces() {
+  intervention_.reset();
+  if (binding_.is_bound())
+    binding_.Close();
+}

chrome/browser/android/oom_intervention/oom_intervention_tab_helper.h

@@ -77,6 +77,8 @@ class OomInterventionTabHelper
 
   void ResetInterventionState();
 
+  void ResetInterfaces();
+
   bool navigation_started_ = false;
   base::Optional<base::TimeTicks> near_oom_detected_time_;
   std::unique_ptr<NearOomMonitor::Subscription> subscription_;