Fix a bug in ImportingData Overlay which cause crash when importing data multiple times.

Fix the problem when force closing the tab while importing.

BUG=49095
TEST=None

Review URL: http://codereview.chromium.org/3167028

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@56933 0039d316-1c4b-4281-b951-d872f2087c98

chrome/browser/dom_ui/import_data_handler.cc

@@ -22,11 +22,13 @@ ImportDataHandler::ImportDataHandler() {
 }
 
 ImportDataHandler::~ImportDataHandler() {
+  if (importer_host_ != NULL) {
+    importer_host_->SetObserver(NULL);
+    importer_host_ = NULL;
+  }
 }
 
 void ImportDataHandler::Initialize() {
-  importer_host_ = new ImporterHost();
-  DetectSupportedBrowsers();
 }
 
 void ImportDataHandler::GetLocalizedValues(
@@ -53,10 +55,17 @@ void ImportDataHandler::GetLocalizedValues(
 }
 
 void ImportDataHandler::RegisterMessages() {
+  dom_ui_->RegisterMessageCallback(
+      "loadImporter", NewCallback(this, &ImportDataHandler::LoadImporter));
   dom_ui_->RegisterMessageCallback(
       "importData", NewCallback(this, &ImportDataHandler::ImportData));
 }
 
+void ImportDataHandler::LoadImporter(const ListValue* args) {
+  importer_host_ = new ImporterHost();
+  DetectSupportedBrowsers();
+}
+
 void ImportDataHandler::DetectSupportedBrowsers() {
   ListValue supported_browsers;
   int profiles_count = importer_host_->GetAvailableProfileCount();
@@ -120,4 +129,5 @@ void ImportDataHandler::ImportItemEnded(importer::ImportItem item) {
 
 void ImportDataHandler::ImportEnded() {
   dom_ui_->CallJavascriptFunction(L"ImportDataOverlay.dismiss");
+  importer_host_ = NULL;
 }

chrome/browser/dom_ui/import_data_handler.h

@@ -24,6 +24,7 @@ class ImportDataHandler : public OptionsPageUIHandler,
   virtual void RegisterMessages();
 
  private:
+  void LoadImporter(const ListValue* args);
   void DetectSupportedBrowsers();
   void ImportData(const ListValue* args);
 
@@ -34,7 +35,7 @@ class ImportDataHandler : public OptionsPageUIHandler,
   virtual void ImportEnded();
 
   // If non-null it means importing is in progress. ImporterHost takes care
-  // of deleting itself when done.import.
+  // of deleting itself when done import.
   scoped_refptr<ImporterHost> importer_host_;
 
   DISALLOW_COPY_AND_ASSIGN(ImportDataHandler);

chrome/browser/resources/options/import_data_overlay.js

@@ -109,6 +109,10 @@ cr.define('options', function() {
     },
   };
 
+  ImportDataOverlay.loadImporter = function() {
+    chrome.send('loadImporter');
+  };
+
   ImportDataOverlay.updateSupportedBrowsers = function(browsers) {
     ImportDataOverlay.getInstance().updateSupportedBrowsers_(browsers);
   };
@@ -141,8 +145,8 @@ cr.define('options', function() {
   };
 
   ImportDataOverlay.dismiss = function() {
-    OptionsPage.clearOverlays();
     ImportDataOverlay.setImportingState(false);
+    OptionsPage.clearOverlays();
   }
 
   // Export

chrome/browser/resources/options/personal_options.js

@@ -68,7 +68,8 @@ cr.define('options', function() {
           OptionsPage.showOverlay('stopSyncingOverlay');
         };
         $('import_data').onclick = function(event) {
-            OptionsPage.showOverlay('importDataOverlay');
+          ImportDataOverlay.loadImporter();
+          OptionsPage.showOverlay('importDataOverlay');
         };
       }