[ObjC ARC] Converts ios/chrome/browser/passwords:unit_tests to ARC.

ios/web/public/test/test_web_state.mm

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "ios/web/public/test/test_web_state.h"
 
 #include <stdint.h>
 
 #include "base/callback.h"
+#include "ios/web/public/web_state/web_state_observer.h"
 
 namespace web {
 
+void TestWebState::AddObserver(WebStateObserver* observer) {
+  observers_.AddObserver(observer);
+}
+
+void TestWebState::RemoveObserver(WebStateObserver* observer) {
+  observers_.RemoveObserver(observer);
+}
+
 TestWebState::TestWebState()
     : web_usage_enabled_(false),
       is_loading_(false),
       trust_level_(kAbsolute),
       content_is_html_(true) {}
 
-TestWebState::~TestWebState() = default;
+TestWebState::~TestWebState() {
+  for (auto& observer : observers_)
+    observer.WebStateDestroyed();
+  for (auto& observer : observers_)
+    observer.ResetWebState();
+};
 
 WebStateDelegate* TestWebState::GetDelegate() {
   return nil;
 }
 
 void TestWebState::SetDelegate(WebStateDelegate* delegate) {}
 
 BrowserState* TestWebState::GetBrowserState() const {
   return nullptr;
 }
@@ skipping 115 matching lines @@
 service_manager::InterfaceRegistry* TestWebState::GetMojoInterfaceRegistry() {
   return nullptr;
 }
 
 base::WeakPtr<WebState> TestWebState::AsWeakPtr() {
   NOTREACHED();
   return base::WeakPtr<WebState>();
 }
 
 }  // namespace web