Cleanup in InstantTab and InstantController

chrome/browser/ui/search/instant_tab.cc

Index: chrome/browser/ui/search/instant_tab.cc
diff --git a/chrome/browser/ui/search/instant_tab.cc b/chrome/browser/ui/search/instant_tab.cc
index dea3f31c2427ca2e8dfff6ea8d108473bd6e264e..9e47432fb306c485cecb036f69a9e0c42ef906ca 100644
--- a/chrome/browser/ui/search/instant_tab.cc
+++ b/chrome/browser/ui/search/instant_tab.cc
@@ -10,8 +10,10 @@
 #include "content/public/browser/render_frame_host.h"
 #include "content/public/browser/web_contents.h"
 
-InstantTab::Delegate::~Delegate() {
-}
+InstantTab::Delegate::~Delegate() {}
+
+InstantTab::InstantTab(Delegate* delegate, content::WebContents* web_contents)
+    : delegate_(delegate), pending_web_contents_(web_contents) {}
 
 InstantTab::~InstantTab() {
   if (web_contents()) {
@@ -20,27 +22,13 @@ InstantTab::~InstantTab() {
   }
 }
 
-bool InstantTab::supports_instant() const {
-  return web_contents() &&
-      SearchTabHelper::FromWebContents(web_contents())->SupportsInstant();
-}
-
-bool InstantTab::IsLocal() const {
-  return web_contents() &&
-      web_contents()->GetURL() == GURL(chrome::kChromeSearchLocalNtpUrl);
-}
-
-InstantTab::InstantTab(Delegate* delegate)
-    : delegate_(delegate) {
-}
-
-void InstantTab::Init(content::WebContents* new_web_contents) {
-  ClearContents();
-
-  if (!new_web_contents)
+void InstantTab::Init() {
+  if (!pending_web_contents_)
     return;
 
-  Observe(new_web_contents);
+  Observe(pending_web_contents_);
+  pending_web_contents_ = nullptr;
+
   SearchModel* model =
       SearchTabHelper::FromWebContents(web_contents())->model();
   model->AddObserver(this);
@@ -54,13 +42,12 @@ void InstantTab::DidCommitProvisionalLoadForFrame(
     content::RenderFrameHost* render_frame_host,
     const GURL& url,
     ui::PageTransition /* transition_type */) {
-  if (!render_frame_host->GetParent()) {
+  if (!render_frame_host->GetParent())
     delegate_->InstantTabAboutToNavigateMainFrame(web_contents(), url);
-  }
 }
 
 void InstantTab::ModelChanged(const SearchModel::State& old_state,
-                               const SearchModel::State& new_state) {
+                              const SearchModel::State& new_state) {
   if (old_state.instant_support != new_state.instant_support)
     InstantSupportDetermined(new_state.instant_support == INSTANT_SUPPORT_YES);
 }
@@ -69,15 +56,12 @@ void InstantTab::InstantSupportDetermined(bool supports_instant) {
   delegate_->InstantSupportDetermined(web_contents(), supports_instant);
 
   // If the page doesn't support Instant, stop listening to it.
-  if (!supports_instant)
-    ClearContents();
-}
+  if (!supports_instant) {
+    if (web_contents()) {
+      SearchTabHelper::FromWebContents(web_contents())->model()->RemoveObserver(
+          this);
+    }
 
-void InstantTab::ClearContents() {
-  if (web_contents()) {
-    SearchTabHelper::FromWebContents(web_contents())->model()->RemoveObserver(
-        this);
+    Observe(nullptr);
   }
-
-  Observe(NULL);
 }