[iOS Clean] Added JavaScript dialog support.

ios/clean/chrome/browser/ui/dialogs/java_script_dialogs/java_script_dialog_coordinator.mm

+// Copyright 2017 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.
+
+#import "ios/clean/chrome/browser/ui/dialogs/java_script_dialogs/java_script_dialog_coordinator.h"
+
+#import "ios/clean/chrome/browser/ui/commands/java_script_dialog_commands.h"
+#import "ios/clean/chrome/browser/ui/dialogs/dialog_coordinator+subclassing.h"
+#import "ios/clean/chrome/browser/ui/dialogs/java_script_dialogs/java_script_dialog_mediator.h"
+#import "ios/clean/chrome/browser/ui/dialogs/java_script_dialogs/java_script_dialog_request.h"
+#import "ios/clean/chrome/browser/ui/overlay_service/browser_coordinator+overlay_support.h"
+#import "ios/clean/chrome/browser/ui/overlay_service/overlay_service.h"
+#import "ios/shared/chrome/browser/ui/browser_list/browser.h"
+#import "ios/shared/chrome/browser/ui/commands/command_dispatcher.h"
+#import "ios/shared/chrome/browser/ui/coordinators/browser_coordinator+internal.h"
+
+#if !defined(__has_feature) || !__has_feature(objc_arc)
+#error "This file requires ARC support."
+#endif
+
+@interface JavaScriptDialogCoordinator ()<JavaScriptDialogDismissalCommands> {
+  // Backing object for property of same name (from Subclassing category).
+  DialogMediator* _mediator;
+}
+
+// The dispatcher to use for JavaScriptdialogDismissalCommands.
+@property(nonatomic, readonly) id<JavaScriptDialogDismissalCommands>
+    dismissalDispatcher;
+// The request for this dialog.
+@property(nonatomic, strong) JavaScriptDialogRequest* request;
+
+@end
+
+@implementation JavaScriptDialogCoordinator
+@synthesize request = _request;
+
+- (instancetype)initWithRequest:(JavaScriptDialogRequest*)request {
+  DCHECK(request);
+  if ((self = [super init])) {
+    _request = request;
+  }
+  return self;
+}
+
+#pragma mark - Accessors
+
+- (id<JavaScriptDialogDismissalCommands>)dismissalDispatcher {
+  return static_cast<id<JavaScriptDialogDismissalCommands>>(
+      self.browser->dispatcher());
+}
+
+#pragma mark - BrowserCoordinator
+
+- (void)start {
+  _mediator = [[JavaScriptDialogMediator alloc]
+      initWithRequest:self.request
+           dispatcher:self.dismissalDispatcher];
+  [self.browser->dispatcher()
+      startDispatchingToTarget:self
+                   forProtocol:@protocol(JavaScriptDialogDismissalCommands)];
+  [super start];
+}
+
+- (void)stop {
+  if (self.started)
+    [self.browser->dispatcher() stopDispatchingToTarget:self];
+  [super stop];
+}
+
+#pragma mark - JavaScriptDialogDismisalCommands
+
+- (void)dismissJavaScriptDialog {
+  [self stop];
+}
+
+@end
+
+@implementation JavaScriptDialogCoordinator (OverlaySupport)
+
+- (void)cancelOverlay {
+  [self.request finishRequestWithSuccess:NO userInput:nil];
+}
+
+@end
+
+@implementation JavaScriptDialogCoordinator (Subclassing)
+
+- (DialogMediator*)mediator {
+  return _mediator;
+}
+
+@end