Make AssistantWebView compatible w/ single- and multi-process mash.

AssistantWebView is the host for embedding the web contents used by
Assistant Settings and Reminders. Previously, AssistantWebView did
not handle either single- or multi-process mash, so the web contents
would not be embedded.

Now, we use Content Service which works in both single- and multi-
process mash in the same pattern established for AppList in:
https://chromium-review.googlesource.com/c/chromium/src/+/1269622

This required adding a few new abilities to NavigableContents that
Assistant has the need for:
- Adding min/max size for auto resizing.
- Adding ability to navigate backwards in history stack.
- Adding handling for target="_blank" links.

Still TODO: Do the same for the Assistant cards that are embedded in
Assistant's UiElementContainerView. Once this is complete, we will be
able to remove WebContentsManager and associated classes/logic :)

Bug: b:78078693
Change-Id: I4dd19a0a4c9506fc6b7f065d54fc1a75132d278f
Reviewed-on: https://chromium-review.googlesource.com/c/1313745
Commit-Queue: David Black <dmblack@google.com>
Reviewed-by: Xiaohui Chen <xiaohuic@chromium.org>
Reviewed-by: Daniel Cheng <dcheng@chromium.org>
Reviewed-by: Dmitry Gozman <dgozman@chromium.org>
Reviewed-by: Xiyuan Xia <xiyuan@chromium.org>
Reviewed-by: Ken Rockot <rockot@google.com>
Cr-Commit-Position: refs/heads/master@{#606966}

ash/assistant/assistant_controller.cc

@@ -24,6 +24,8 @@
 #include "base/bind.h"
 #include "base/memory/scoped_refptr.h"
 #include "base/unguessable_token.h"
+#include "services/content/public/mojom/constants.mojom.h"
+#include "services/service_manager/public/cpp/connector.h"
 
 namespace ash {
 
@@ -309,6 +311,28 @@ void AssistantController::OpenUrl(const GURL& url, bool from_server) {
   NotifyUrlOpened(url, from_server);
 }
 
+void AssistantController::GetNavigableContentsFactory(
+    content::mojom::NavigableContentsFactoryRequest request) {
+  const mojom::UserSession* user_session =
+      Shell::Get()->session_controller()->GetUserSession(0);
+
+  if (!user_session) {
+    LOG(WARNING) << "Unable to retrieve active user session.";
+    return;
+  }
+
+  const std::string& service_user_id = user_session->user_info->service_user_id;
+
+  if (service_user_id.empty()) {
+    LOG(ERROR) << "Unable to retrieve service user id.";
+    return;
+  }
+
+  Shell::Get()->connector()->BindInterface(
+      service_manager::Identity(content::mojom::kServiceName, service_user_id),
+      std::move(request));
+}
+
 void AssistantController::NotifyConstructed() {
   for (AssistantControllerObserver& observer : observers_)
     observer.OnAssistantControllerConstructed();

ash/assistant/assistant_controller.h

@@ -27,6 +27,7 @@
 #include "chromeos/services/assistant/public/mojom/assistant.mojom.h"
 #include "mojo/public/cpp/bindings/binding_set.h"
 #include "mojo/public/cpp/bindings/interface_ptr_set.h"
+#include "services/content/public/mojom/navigable_contents_factory.mojom.h"
 #include "ui/gfx/geometry/rect.h"
 
 namespace base {
@@ -135,6 +136,11 @@ class ASH_EXPORT AssistantController
   // to deep links which may cause deviation from this behavior.
   void OpenUrl(const GURL& url, bool from_server = false);
 
+  // Acquires a NavigableContentsFactory from the Content Service to allow
+  // Assistant to display embedded web contents.
+  void GetNavigableContentsFactory(
+      content::mojom::NavigableContentsFactoryRequest request);
+
   AssistantCacheController* cache_controller() {
     DCHECK(assistant_cache_controller_);
     return assistant_cache_controller_.get();

ash/assistant/ui/assistant_web_view.h

@@ -13,13 +13,10 @@
 #include "ash/assistant/ui/caption_bar.h"
 #include "base/macros.h"
 #include "base/optional.h"
+#include "mojo/public/cpp/bindings/binding.h"
+#include "services/content/public/cpp/navigable_contents.h"
 #include "ui/aura/window_observer.h"
 #include "ui/views/view.h"
-#include "ui/views/view_observer.h"
-
-namespace base {
-class UnguessableToken;
-}  // namespace base
 
 namespace ash {
 
@@ -27,13 +24,13 @@ class AssistantController;
 
 // AssistantWebView is a child of AssistantBubbleView which allows Assistant UI
 // to render remotely hosted content within its bubble. It provides a CaptionBar
-// for window level controls and a WebView/ServerRemoteViewHost for embedding
-// web contents.
+// for window level controls and embeds web contents with help from the Content
+// Service.
 class AssistantWebView : public views::View,
-                         public views::ViewObserver,
                          public aura::WindowObserver,
                          public AssistantControllerObserver,
-                         public CaptionBarDelegate {
+                         public CaptionBarDelegate,
+                         public content::NavigableContentsObserver {
  public:
   explicit AssistantWebView(AssistantController* assistant_controller);
   ~AssistantWebView() override;
@@ -44,9 +41,6 @@ class AssistantWebView : public views::View,
   int GetHeightForWidth(int width) const override;
   void ChildPreferredSizeChanged(views::View* child) override;
 
-  // views::ViewObserver:
-  void OnViewIsDeleting(views::View* view) override;
-
   // views::WindowObserver:
   void OnWindowBoundsChanged(aura::Window* window,
                              const gfx::Rect& old_bounds,
@@ -62,32 +56,31 @@ class AssistantWebView : public views::View,
       assistant::util::DeepLinkType type,
       const std::map<std::string, std::string>& params) override;
 
+  // content::NavigableContentsObserver:
+  void DidAutoResizeView(const gfx::Size& new_size) override;
+  void DidStopLoading() override;
+  void DidSuppressNavigation(const GURL& url,
+                             WindowOpenDisposition disposition,
+                             bool from_user_gesture) override;
+
  private:
   void InitLayout();
-  void OnWebContentsReady(
-      const base::Optional<base::UnguessableToken>& embed_token);
-  void ReleaseWebContents();
+  void RemoveContents();
 
   AssistantController* const assistant_controller_;  // Owned by Shell.
 
   CaptionBar* caption_bar_;  // Owned by view hierarchy.
 
-  // In Mash, |content_view_| is owned by the view hierarchy. Otherwise, the
-  // view is owned by the WebContentsManager.
-  views::View* content_view_ = nullptr;
-  gfx::NativeView native_content_view_ = nullptr;
+  content::mojom::NavigableContentsFactoryPtr contents_factory_;
+  std::unique_ptr<content::NavigableContents> contents_;
 
   // Our contents are drawn to a layer that is not masked by our widget's layer.
   // This causes our contents to ignore the corner radius that we have set on
   // the widget. To address this, we apply a separate layer mask to the
-  // contents' layer enforcing our desired corner radius.
-  std::unique_ptr<ui::LayerOwner> content_view_mask_;
-
-  // Uniquely identifies web contents owned by WebContentsManager.
-  base::Optional<base::UnguessableToken> web_contents_id_token_;
+  // contents' native view layer enforcing our desired corner radius.
+  std::unique_ptr<ui::LayerOwner> contents_mask_;
 
-  // Weak pointer factory used for web contents rendering requests.
-  base::WeakPtrFactory<AssistantWebView> web_contents_request_factory_;
+  base::WeakPtrFactory<AssistantWebView> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(AssistantWebView);
 };

ash/manifest.json

@@ -69,6 +69,7 @@
         "*": [ "accessibility", "app" ],
         "ash_pref_connector": [ "pref_connector" ],
         "catalog": [ "directory" ],
+        "content": [ "navigation" ],
         "device": [
           "device:bluetooth_system",
           "device:fingerprint"

content/browser/content_service_delegate_impl.cc

@@ -30,7 +30,11 @@ class NavigableContentsDelegateImpl : public content::NavigableContentsDelegate,
       const mojom::NavigableContentsParams& params,
       mojom::NavigableContentsClient* client)
       : client_(client),
-        enable_view_auto_resize_(params.enable_view_auto_resize) {
+        enable_view_auto_resize_(params.enable_view_auto_resize),
+        auto_resize_min_size_(
+            params.auto_resize_min_size.value_or(gfx::Size(1, 1))),
+        auto_resize_max_size_(
+            params.auto_resize_max_size.value_or(gfx::Size(INT_MAX, INT_MAX))) {
     WebContents::CreateParams create_params(browser_context);
     web_contents_ = WebContents::Create(create_params);
     WebContentsObserver::Observe(web_contents_.get());
@@ -63,7 +67,39 @@ class NavigableContentsDelegateImpl : public content::NavigableContentsDelegate,
     web_contents_->GetController().LoadURLWithParams(load_url_params);
   }
 
+  void GoBack(
+      content::mojom::NavigableContents::GoBackCallback callback) override {
+    content::NavigationController& controller = web_contents_->GetController();
+    if (controller.CanGoBack()) {
+      std::move(callback).Run(/*success=*/true);
+      controller.GoBack();
+    } else {
+      std::move(callback).Run(/*success=*/false);
+    }
+  }
+
   // WebContentsDelegate:
+  bool ShouldCreateWebContents(
+      content::WebContents* web_contents,
+      content::RenderFrameHost* opener,
+      content::SiteInstance* source_site_instance,
+      int32_t route_id,
+      int32_t main_frame_route_id,
+      int32_t main_frame_widget_route_id,
+      content::mojom::WindowContainerType window_container_type,
+      const GURL& opener_url,
+      const std::string& frame_name,
+      const GURL& target_url,
+      const std::string& partition_id,
+      content::SessionStorageNamespace* session_storage_namespace) override {
+    // This method is invoked when attempting to open links in a new tab, e.g.:
+    // <a href="https://www.google.com/" target="_blank">Link</a>
+    client_->DidSuppressNavigation(target_url,
+                                   WindowOpenDisposition::NEW_FOREGROUND_TAB,
+                                   /*from_user_gesture=*/true);
+    return false;
+  }
+
   WebContents* OpenURLFromTab(WebContents* source,
                               const OpenURLParams& params) override {
     client_->DidSuppressNavigation(params.url, params.disposition,
@@ -82,7 +118,7 @@ class NavigableContentsDelegateImpl : public content::NavigableContentsDelegate,
                              RenderViewHost* new_host) override {
     if (enable_view_auto_resize_ && web_contents_->GetRenderWidgetHostView()) {
       web_contents_->GetRenderWidgetHostView()->EnableAutoResize(
-          gfx::Size(1, 1), gfx::Size(INT_MAX, INT_MAX));
+          auto_resize_min_size_, auto_resize_max_size_);
     }
   }
 
@@ -102,6 +138,8 @@ class NavigableContentsDelegateImpl : public content::NavigableContentsDelegate,
   mojom::NavigableContentsClient* const client_;
 
   const bool enable_view_auto_resize_;
+  const gfx::Size auto_resize_min_size_;
+  const gfx::Size auto_resize_max_size_;
 
   DISALLOW_COPY_AND_ASSIGN(NavigableContentsDelegateImpl);
 };

services/content/navigable_contents_delegate.h

@@ -33,6 +33,12 @@ class NavigableContentsDelegate {
 
   // Navigates the content object to a new URL.
   virtual void Navigate(const GURL& url, mojom::NavigateParamsPtr params) = 0;
+
+  // Attempts to navigate the web contents back in its history stack. The
+  // supplied |callback| is run to indicate success/failure of the attempt. The
+  // navigation attempt will fail if the history stack is empty.
+  virtual void GoBack(
+      content::mojom::NavigableContents::GoBackCallback callback) = 0;
 };
 
 }  // namespace content

services/content/navigable_contents_impl.cc

@@ -53,6 +53,11 @@ void NavigableContentsImpl::Navigate(const GURL& url,
   delegate_->Navigate(url, std::move(params));
 }
 
+void NavigableContentsImpl::GoBack(
+    mojom::NavigableContents::GoBackCallback callback) {
+  delegate_->GoBack(std::move(callback));
+}
+
 void NavigableContentsImpl::CreateView(bool in_service_process,
                                        CreateViewCallback callback) {
   DCHECK(native_content_view_);

services/content/navigable_contents_impl.h

@@ -38,6 +38,7 @@ class NavigableContentsImpl : public mojom::NavigableContents {
  private:
   // mojom::NavigableContents:
   void Navigate(const GURL& url, mojom::NavigateParamsPtr params) override;
+  void GoBack(mojom::NavigableContents::GoBackCallback callback) override;
   void CreateView(bool in_service_process,
                   CreateViewCallback callback) override;
 

services/content/public/cpp/navigable_contents.cc

@@ -51,6 +51,11 @@ void NavigableContents::NavigateWithParams(const GURL& url,
   contents_->Navigate(url, std::move(params));
 }
 
+void NavigableContents::GoBack(
+    content::mojom::NavigableContents::GoBackCallback callback) {
+  contents_->GoBack(std::move(callback));
+}
+
 void NavigableContents::DidFinishNavigation(
     const GURL& url,
     bool is_main_frame,

services/content/public/cpp/navigable_contents.h

@@ -52,6 +52,11 @@ class COMPONENT_EXPORT(CONTENT_SERVICE_CPP) NavigableContents
   void Navigate(const GURL& url);
   void NavigateWithParams(const GURL& url, mojom::NavigateParamsPtr params);
 
+  // Attempts to navigate back in the web contents' history stack. The supplied
+  // |callback| is run to indicate success/failure of the navigation attempt.
+  // The navigation attempt will fail if the history stack is empty.
+  void GoBack(content::mojom::NavigableContents::GoBackCallback callback);
+
  private:
   // mojom::NavigableContentsClient:
   void DidFinishNavigation(

services/content/public/cpp/test/fake_navigable_contents.cc

@@ -36,6 +36,11 @@ void FakeNavigableContents::Navigate(const GURL& url,
   client_->DidStopLoading();
 }
 
+void FakeNavigableContents::GoBack(
+    mojom::NavigableContents::GoBackCallback callback) {
+  std::move(callback).Run(false /* success */);
+}
+
 void FakeNavigableContents::CreateView(bool in_service_process,
                                        CreateViewCallback callback) {
   auto token = base::UnguessableToken::Create();

services/content/public/cpp/test/fake_navigable_contents.h

@@ -36,6 +36,7 @@ class FakeNavigableContents : public mojom::NavigableContents {
  private:
   // mojom::NavigableContents:
   void Navigate(const GURL& url, mojom::NavigateParamsPtr params) override;
+  void GoBack(mojom::NavigableContents::GoBackCallback callback) override;
   void CreateView(bool in_service_process,
                   CreateViewCallback callback) override;
 

services/content/public/mojom/navigable_contents.mojom

@@ -26,6 +26,11 @@ interface NavigableContents {
   // Initiates a navigation to |url|.
   Navigate(url.mojom.Url url, NavigateParams params);
 
+  // Attempts to navigate the web contents back in its history stack. The
+  // supplied |callback| is run to indicate success/failure of the attempt. The
+  // navigation attempt will fail if the history stack is empty.
+  GoBack() => (bool success);
+
   // Creates a visual representation of the navigated contents, which is
   // maintained by the Content Service. Responds with a |embed_token| which can
   // be given to Mus in order to authorize embedding of that visual

services/content/public/mojom/navigable_contents_factory.mojom

@@ -5,6 +5,7 @@
 module content.mojom;
 
 import "services/content/public/mojom/navigable_contents.mojom";
+import "ui/gfx/geometry/mojo/geometry.mojom";
 
 // Parameters used to configure a newly created NavigableContents.
 struct NavigableContentsParams {
@@ -13,6 +14,14 @@ struct NavigableContentsParams {
   // |DidAutoResizeView()| notifications whenever such resizing happens.
   bool enable_view_auto_resize = false;
 
+  // Specifies the minimum size for auto resizing.
+  // Defaults to (1, 1).
+  gfx.mojom.Size? auto_resize_min_size;
+
+  // Specifies the maximum size for auto resizing.
+  // Defaults to (INT_MAX, INT_MAX).
+  gfx.mojom.Size? auto_resize_max_size;
+
   // Indicates that the client wants to control how navigation requests are
   // handled within the created NavigableContents. Any attempt to navigate the
   // NavigableContents by any means other than an explicit call to

services/content/service_unittest.cc

@@ -62,6 +62,11 @@ class TestNavigableContentsDelegate : public NavigableContentsDelegate {
       navigation_callback_.Run();
   }
 
+  void GoBack(
+      content::mojom::NavigableContents::GoBackCallback callback) override {
+    std::move(callback).Run(false /* success */);
+  }
+
   gfx::NativeView GetNativeView() override { return nullptr; }
 
  private:

services/service_manager/public/cpp/connector.h

@@ -110,6 +110,11 @@ class SERVICE_MANAGER_PUBLIC_CPP_EXPORT Connector {
     BindInterface(target, Interface::Name_, std::move(pipe.handle1));
   }
   template <typename Interface>
+  void BindInterface(const Identity& target,
+                     mojo::InterfaceRequest<Interface> request) {
+    BindInterface(target, Interface::Name_, request.PassMessagePipe());
+  }
+  template <typename Interface>
   void BindInterface(const std::string& name,
                      mojo::InterfacePtr<Interface>* ptr) {
     return BindInterface(Identity(name, mojom::kInheritUserID), ptr);