[ObjC ARC] Converts part of ios/web to ARC.

Converts web_state-related files to ARC.

Notable issues:
 - Had to fix WebUIMojoTest.MessageExchange. See comment.

Bug: 
Change-Id: Ia8a58433ab82d67ebae4f61b8c4ea954f84df202
Reviewed-on: https://chromium-review.googlesource.com/570402
Commit-Queue: Stepan Khapugin <stkhapugin@chromium.org>
Reviewed-by: Eugene But <eugenebut@chromium.org>
Cr-Commit-Position: refs/heads/master@{#487544}

ios/web/BUILD.gn

@@ -252,6 +252,16 @@ source_set("web_arc") {
     "web_state/ui/wk_web_view_configuration_provider.mm",
     "web_state/web_controller_observer_bridge.h",
     "web_state/web_controller_observer_bridge.mm",
+    "web_state/web_state.mm",
+    "web_state/web_state_delegate.mm",
+    "web_state/web_state_delegate_bridge.mm",
+    "web_state/web_state_impl.h",
+    "web_state/web_state_impl.mm",
+    "web_state/web_state_observer.mm",
+    "web_state/web_state_observer_bridge.mm",
+    "web_state/web_state_policy_decider.mm",
+    "web_state/web_state_weak_ptr_factory.h",
+    "web_state/web_state_weak_ptr_factory.mm",
     "web_state/web_view_internal_creation_util.h",
     "web_state/web_view_internal_creation_util.mm",
     "web_state/wk_web_view_security_util.h",
@@ -326,16 +336,6 @@ source_set("web") {
     "web_state/ui/crw_web_controller.mm",
     "web_state/ui/crw_web_controller_container_view.h",
     "web_state/ui/crw_web_controller_container_view.mm",
-    "web_state/web_state.mm",
-    "web_state/web_state_delegate.mm",
-    "web_state/web_state_delegate_bridge.mm",
-    "web_state/web_state_impl.h",
-    "web_state/web_state_impl.mm",
-    "web_state/web_state_observer.mm",
-    "web_state/web_state_observer_bridge.mm",
-    "web_state/web_state_policy_decider.mm",
-    "web_state/web_state_weak_ptr_factory.h",
-    "web_state/web_state_weak_ptr_factory.mm",
   ]
 
   libs = [

ios/web/web_state/web_state.mm

@@ -4,6 +4,10 @@
 
 #import "ios/web/public/web_state/web_state.h"
 
+#if !defined(__has_feature) || !__has_feature(objc_arc)
+#error "This file requires ARC support."
+#endif
+
 namespace web {
 
 WebState::CreateParams::CreateParams(web::BrowserState* browser_state)

ios/web/web_state/web_state_delegate.mm

@@ -6,6 +6,10 @@
 
 #import "ios/web/public/web_state/web_state.h"
 
+#if !defined(__has_feature) || !__has_feature(objc_arc)
+#error "This file requires ARC support."
+#endif
+
 namespace web {
 
 WebStateDelegate::WebStateDelegate() {}

ios/web/web_state/web_state_delegate_bridge.mm

@@ -7,6 +7,10 @@
 #include "base/logging.h"
 #import "ios/web/public/web_state/context_menu_params.h"
 
+#if !defined(__has_feature) || !__has_feature(objc_arc)
+#error "This file requires ARC support."
+#endif
+
 namespace web {
 
 WebStateDelegateBridge::WebStateDelegateBridge(id<CRWWebStateDelegate> delegate)

ios/web/web_state/web_state_impl.mm

@@ -44,6 +44,10 @@
 #include "net/http/http_response_headers.h"
 #include "ui/gfx/image/image.h"
 
+#if !defined(__has_feature) || !__has_feature(objc_arc)
+#error "This file requires ARC support."
+#endif
+
 namespace web {
 
 /* static */
@@ -173,7 +177,7 @@ CRWWebController* WebStateImpl::GetWebController() {
 
 void WebStateImpl::SetWebController(CRWWebController* web_controller) {
   [web_controller_ close];
-  web_controller_.reset([web_controller retain]);
+  web_controller_.reset(web_controller);
 }
 
 void WebStateImpl::OnTitleChanged() {

ios/web/web_state/web_state_observer.mm

@@ -7,6 +7,10 @@
 #include "ios/web/public/load_committed_details.h"
 #import "ios/web/public/web_state/web_state.h"
 
+#if !defined(__has_feature) || !__has_feature(objc_arc)
+#error "This file requires ARC support."
+#endif
+
 namespace web {
 
 WebStateObserver::WebStateObserver(WebState* web_state) : web_state_(nullptr) {

ios/web/web_state/web_state_observer_bridge.mm

@@ -4,6 +4,10 @@
 
 #import "ios/web/public/web_state/web_state_observer_bridge.h"
 
+#if !defined(__has_feature) || !__has_feature(objc_arc)
+#error "This file requires ARC support."
+#endif
+
 namespace web {
 
 WebStateObserverBridge::WebStateObserverBridge(web::WebState* webState,

ios/web/web_state/web_state_policy_decider.mm

@@ -7,6 +7,10 @@
 #import "ios/web/public/web_state/web_state.h"
 #import "ios/web/web_state/web_state_impl.h"
 
+#if !defined(__has_feature) || !__has_feature(objc_arc)
+#error "This file requires ARC support."
+#endif
+
 namespace web {
 
 WebStatePolicyDecider::WebStatePolicyDecider(WebState* web_state)

ios/web/web_state/web_state_weak_ptr_factory.mm

@@ -6,6 +6,10 @@
 
 #import "ios/web/public/web_state/web_state.h"
 
+#if !defined(__has_feature) || !__has_feature(objc_arc)
+#error "This file requires ARC support."
+#endif
+
 namespace web {
 
 // static

ios/web/webui/web_ui_mojo_inttest.mm

@@ -147,6 +147,23 @@ class WebUIMojoTest : public WebIntTest {
         new TestWebUIControllerFactory(ui_handler_.get()));
   }
 
+  void TearDown() override {
+    @autoreleasepool {
+      // WebState owns CRWWebUIManager. When WebState is destroyed,
+      // CRWWebUIManager is autoreleased and will be destroyed upon autorelease
+      // pool purge. However in this test, WebTest destructor is called before
+      // PlatformTest, thus CRWWebUIManager outlives the WebThreadBundle.
+      // However, CRWWebUIManager owns a URLFetcherImpl, which DCHECKs that its
+      // destructor is called on UI web thread. Hence, URLFetcherImpl has to
+      // outlive the WebThreadBundle, since [NSThread mainThread] will not be
+      // WebThread::UI once WebThreadBundle is destroyed.
+      web_state_.reset();
+      ui_handler_.reset();
+    }
+
+    WebIntTest::TearDown();
+  }
+
   // Returns WebState which loads test WebUI page.
   WebStateImpl* web_state() { return web_state_.get(); }
   // Returns UI handler which communicates with WebUI page.
@@ -167,31 +184,33 @@ class WebUIMojoTest : public WebIntTest {
 #endif
 // TODO(crbug.com/720098): Enable this test on device.
 TEST_F(WebUIMojoTest, MAYBE_MessageExchange) {
-  web_state()->SetWebUsageEnabled(true);
-  web_state()->GetView();  // WebState won't load URL without view.
-  GURL url(
-      url::SchemeHostPort(kTestWebUIScheme, kTestWebUIURLHost, 0).Serialize());
-  NavigationManager::WebLoadParams load_params(url);
-  web_state()->GetNavigationManager()->LoadURLWithParams(load_params);
-
-  // Wait until |TestUIHandler| receives "fin" message from WebUI page.
-  bool fin_received = testing::WaitUntilConditionOrTimeout(kMessageTimeout, ^{
-    // Flush any pending tasks. Don't RunUntilIdle() because
-    // RunUntilIdle() is incompatible with mojo::SimpleWatcher's
-    // automatic arming behavior, which Mojo JS still depends upon.
-    //
-    // TODO(crbug.com/701875): Introduce the full watcher API to JS and get rid
-    // of this hack.
-    base::RunLoop loop;
-    base::ThreadTaskRunnerHandle::Get()->PostTask(FROM_HERE,
-                                                  loop.QuitClosure());
-    loop.Run();
-    return test_ui_handler()->IsFinReceived();
-  });
-
-  ASSERT_TRUE(fin_received);
-  EXPECT_FALSE(web_state()->IsLoading());
-  EXPECT_EQ(url, web_state()->GetLastCommittedURL());
+  @autoreleasepool {
+    web_state()->SetWebUsageEnabled(true);
+    web_state()->GetView();  // WebState won't load URL without view.
+    GURL url(url::SchemeHostPort(kTestWebUIScheme, kTestWebUIURLHost, 0)
+                 .Serialize());
+    NavigationManager::WebLoadParams load_params(url);
+    web_state()->GetNavigationManager()->LoadURLWithParams(load_params);
+
+    // Wait until |TestUIHandler| receives "fin" message from WebUI page.
+    bool fin_received = testing::WaitUntilConditionOrTimeout(kMessageTimeout, ^{
+      // Flush any pending tasks. Don't RunUntilIdle() because
+      // RunUntilIdle() is incompatible with mojo::SimpleWatcher's
+      // automatic arming behavior, which Mojo JS still depends upon.
+      //
+      // TODO(crbug.com/701875): Introduce the full watcher API to JS and get
+      // rid of this hack.
+      base::RunLoop loop;
+      base::ThreadTaskRunnerHandle::Get()->PostTask(FROM_HERE,
+                                                    loop.QuitClosure());
+      loop.Run();
+      return test_ui_handler()->IsFinReceived();
+    });
+
+    ASSERT_TRUE(fin_received);
+    EXPECT_FALSE(web_state()->IsLoading());
+    EXPECT_EQ(url, web_state()->GetLastCommittedURL());
+  }
 }
 
 }  // namespace web