[ios] Remove rootViewController from /download

A method (-controllerForUnhandledContent:) was in CRWWebDelegate when
it belongs in CRWNativeContentProvider protocol.
This helped pull the implementation out of tab.mm and into the BVC,
which can provide a base view controller for presenting UI,
instead of using rootViewController for presentation.

Bug: 791206
Cq-Include-Trybots: master.tryserver.chromium.mac:ios-simulator-cronet;master.tryserver.chromium.mac:ios-simulator-full-configs
Change-Id: If82dcb4f16a64d5e1fef99e2805588e92f2ca4d9
Reviewed-on: https://chromium-review.googlesource.com/807306
Commit-Queue: edchin <edchin@chromium.org>
Reviewed-by: Mark Cogan <marq@chromium.org>
Reviewed-by: edchin <edchin@chromium.org>
Reviewed-by: Eugene But <eugenebut@chromium.org>
Cr-Commit-Position: refs/heads/master@{#521591}

ios/chrome/browser/prerender/preload_controller.mm

@@ -341,6 +341,15 @@ bool IsPrerenderTabEvictionExperimentalGroup() {
   return nil;
 }
 
+// Override the CRWNativeContentProvider methods to cancel any prerenders that
+// require native content.
+- (id<CRWNativeContent>)controllerForUnhandledContentAtURL:(const GURL&)URL
+                                                  webState:
+                                                      (web::WebState*)webState {
+  [self schedulePrerenderCancel];
+  return nil;
+}
+
 #pragma mark -
 #pragma mark Private Methods
 

ios/chrome/browser/tabs/BUILD.gn

@@ -117,7 +117,6 @@ source_set("tabs_internal") {
     "//ios/chrome/browser/ui:ui_internal",
     "//ios/chrome/browser/ui/alert_coordinator",
     "//ios/chrome/browser/ui/commands",
-    "//ios/chrome/browser/ui/download",
     "//ios/chrome/browser/ui/fullscreen",
     "//ios/chrome/browser/ui/fullscreen:legacy_fullscreen",
     "//ios/chrome/browser/ui/overscroll_actions",

ios/chrome/browser/tabs/tab.mm

@@ -78,7 +78,6 @@
 #import "ios/chrome/browser/ui/commands/open_new_tab_command.h"
 #import "ios/chrome/browser/ui/commands/open_url_command.h"
 #import "ios/chrome/browser/ui/commands/show_signin_command.h"
-#import "ios/chrome/browser/ui/download/download_manager_controller.h"
 #import "ios/chrome/browser/ui/fullscreen/fullscreen_features.h"
 #import "ios/chrome/browser/ui/fullscreen/legacy_fullscreen_controller.h"
 #import "ios/chrome/browser/ui/open_in_controller.h"
@@ -654,15 +653,6 @@ void TabInfoBarObserver::OnInfoBarReplaced(infobars::InfoBar* old_infobar,
   return _openInController;
 }
 
-- (id<CRWNativeContent>)controllerForUnhandledContentAtURL:(const GURL&)url {
-  // Shows download manager UI for unhandled content.
-  DownloadManagerController* downloadController =
-      [[DownloadManagerController alloc] initWithWebState:self.webState
-                                              downloadURL:url];
-  [downloadController start];
-  return downloadController;
-}
-
 - (void)handleExportableFile:(net::HttpResponseHeaders*)headers {
   // Only "application/pdf" is supported for now.
   if (self.webState->GetContentsMimeType() != "application/pdf")

ios/chrome/browser/ui/BUILD.gn

@@ -310,6 +310,7 @@ source_set("ui_internal") {
     "//ios/chrome/browser/ui/content_suggestions:content_suggestions_constant",
     "//ios/chrome/browser/ui/context_menu",
     "//ios/chrome/browser/ui/dialogs:dialogs_internal",
+    "//ios/chrome/browser/ui/download",
     "//ios/chrome/browser/ui/elements:elements_internal",
     "//ios/chrome/browser/ui/external_search",
     "//ios/chrome/browser/ui/find_bar",

ios/chrome/browser/ui/browser_view_controller.mm

@@ -138,6 +138,7 @@
 #import "ios/chrome/browser/ui/context_menu/context_menu_coordinator.h"
 #import "ios/chrome/browser/ui/dialogs/dialog_presenter.h"
 #import "ios/chrome/browser/ui/dialogs/java_script_dialog_presenter_impl.h"
+#import "ios/chrome/browser/ui/download/download_manager_controller.h"
 #import "ios/chrome/browser/ui/elements/activity_overlay_coordinator.h"
 #import "ios/chrome/browser/ui/external_file_controller.h"
 #import "ios/chrome/browser/ui/external_search/external_search_coordinator.h"
@@ -3555,6 +3556,17 @@ bubblePresenterForFeature:(const base::Feature&)feature
   return nativeController;
 }
 
+- (id<CRWNativeContent>)controllerForUnhandledContentAtURL:(const GURL&)URL
+                                                  webState:
+                                                      (web::WebState*)webState {
+  DownloadManagerController* downloadController =
+      [[DownloadManagerController alloc] initWithWebState:webState
+                                              downloadURL:URL
+                                       baseViewController:self];
+  [downloadController start];
+  return downloadController;
+}
+
 - (id)nativeControllerForTab:(Tab*)tab {
   id nativeController = tab.webController.nativeController;
   return nativeController ? nativeController : _temporaryNativeController;

ios/chrome/browser/ui/download/download_manager_controller.h

@@ -23,9 +23,10 @@ class WebState;
 
 // Initializes a controller for content from |url| using |webState| to provide
 // the context to open a controller that allows the user to install Google Drive
-// if they don't have it installed.
+// if they don't have it installed. Present UI from |baseViewController|.
 - (instancetype)initWithWebState:(web::WebState*)webState
-                     downloadURL:(const GURL&)url;
+                     downloadURL:(const GURL&)url
+              baseViewController:(UIViewController*)baseViewController;
 
 // Starts loading the data for the file at the url passed into the
 // initializer. This should only be called once, immediately after

ios/chrome/browser/ui/download/download_manager_controller.mm

@@ -490,6 +490,9 @@ class DownloadContentDelegate : public URLFetcherDelegate {
 // downloaded.
 @property(nonatomic) double fractionDownloaded;
 
+// The base view controller from which to present UI.
+@property(nonatomic, readonly, weak) UIViewController* baseViewController;
+
 @end
 
 @implementation DownloadManagerController
@@ -520,9 +523,11 @@ class DownloadContentDelegate : public URLFetcherDelegate {
 @synthesize fileTypeLabelCentered = _fileTypeLabelCentered;
 @synthesize downloadStartedTime = _downloadStartedTime;
 @synthesize fractionDownloaded = _fractionDownloaded;
+@synthesize baseViewController = _baseViewController;
 
 - (instancetype)initWithWebState:(web::WebState*)webState
-                     downloadURL:(const GURL&)url {
+                     downloadURL:(const GURL&)url
+              baseViewController:(UIViewController*)baseViewController {
   self = [super initWithNibName:@"DownloadManagerController" url:url];
   if (self) {
     _downloadManagerId = g_download_manager_id++;
@@ -532,6 +537,7 @@ class DownloadContentDelegate : public URLFetcherDelegate {
     _headFetcherDelegate.reset(new DownloadHeadDelegate(self));
     _contentFetcherDelegate.reset(new DownloadContentDelegate(self));
     _downloadFilePath = base::FilePath();
+    _baseViewController = baseViewController;
 
     [_documentContainer
         setBackgroundColor:UIColorFromRGB(kUndownloadedDocumentColor)];
@@ -1037,19 +1043,15 @@ class DownloadContentDelegate : public URLFetcherDelegate {
 #pragma mark - Errors
 
 - (void)displayUnableToOpenFileDialog {
-  // This code is called inside a xib file, I am using the topViewController.
-  UIViewController* topViewController =
-      [[[UIApplication sharedApplication] keyWindow] rootViewController];
-
   NSString* title =
       l10n_util::GetNSString(IDS_IOS_DOWNLOAD_MANAGER_UNABLE_TO_OPEN_FILE);
   NSString* message =
       l10n_util::GetNSString(IDS_IOS_DOWNLOAD_MANAGER_NO_APP_MESSAGE);
 
-  _alertCoordinator =
-      [[AlertCoordinator alloc] initWithBaseViewController:topViewController
-                                                     title:title
-                                                   message:message];
+  _alertCoordinator = [[AlertCoordinator alloc]
+      initWithBaseViewController:self.baseViewController
+                           title:title
+                         message:message];
 
   StoreKitTabHelper* tabHelper = StoreKitTabHelper::FromWebState(_webState);
   if (tabHelper) {

ios/chrome/browser/ui/download/download_manager_controller_unittest.mm

@@ -63,7 +63,8 @@ class DownloadManagerControllerTest : public ChromeWebTest {
     helper->SetLauncher(mock_launcher);
     _controller =
         [[DownloadManagerController alloc] initWithWebState:web_state()
-                                                downloadURL:kTestURL];
+                                                downloadURL:kTestURL
+                                         baseViewController:nil];
   }
   std::unique_ptr<net::TestURLFetcherFactory> _fetcher_factory;
   __strong DownloadManagerController* _controller;

ios/web/public/test/fakes/test_native_content_provider.mm

@@ -39,4 +39,11 @@
   return nativeContent == _nativeContent.end() ? nil : nativeContent->second;
 }
 
+- (id<CRWNativeContent>)controllerForUnhandledContentAtURL:(const GURL&)URL
+                                                  webState:
+                                                      (web::WebState*)webState {
+  auto nativeContent = _nativeContent.find(URL);
+  return nativeContent == _nativeContent.end() ? nil : nativeContent->second;
+}
+
 @end

ios/web/public/web_state/ui/crw_native_content_provider.h

@@ -40,6 +40,15 @@ class WebState;
                                withError:(NSError*)error
                                   isPost:(BOOL)isPost;
 
+// Returns an autoreleased controller for driving a native view contained
+// within the web content area for unhandled content at |URL|. |webState|
+// triggered the navigation to |URL|.
+// TODO(crbug.com/791806) DEPRECATED! Clients must use web::DownloadController
+// for renderer initiated downloads.
+- (id<CRWNativeContent>)controllerForUnhandledContentAtURL:(const GURL&)URL
+                                                  webState:
+                                                      (web::WebState*)webState;
+
 @end
 
 #endif  // IOS_WEB_PUBLIC_WEB_STATE_UI_CRW_NATIVE_CONTENT_PROVIDER_H_

ios/web/public/web_state/ui/crw_web_delegate.h

@@ -60,12 +60,6 @@ class GURL;
 - (BOOL)webController:(CRWWebController*)webController
     shouldOpenExternalURL:(const GURL&)URL;
 
-// Called to ask the delegate for a controller to display the given url,
-// which contained content that the UIWebView couldn't display. Returns
-// the native controller to display if the delegate can handle the url,
-// or nil otherwise.
-- (id<CRWNativeContent>)controllerForUnhandledContentAtURL:(const GURL&)url;
-
 // Called to retrieve the height of any header that is overlaying on top of the
 // web view. This can be used to implement, for e.g. a toolbar that changes
 // height dynamically. Returning a non-zero height affects the visible frame

ios/web/web_state/ui/crw_web_controller.mm

@@ -2955,11 +2955,10 @@ registerLoadRequestForURL:(const GURL&)requestURL
         ![MIMEType isEqualToString:@"application/vnd.apple.pkpass"]) {
       // This block is executed to handle legacy download navigation.
       const GURL errorGURL = net::GURLWithNSURL(errorURL);
-      if (errorGURL.is_valid() &&
-          [_delegate respondsToSelector:@selector
-                     (controllerForUnhandledContentAtURL:)]) {
+      if (errorGURL.is_valid()) {
         id<CRWNativeContent> controller =
-            [_delegate controllerForUnhandledContentAtURL:errorGURL];
+            [_nativeProvider controllerForUnhandledContentAtURL:errorGURL
+                                                       webState:self.webState];
         if (controller) {
           [self loadCompleteWithSuccess:NO forNavigation:navigation];
           [self removeWebView];