[ios] BubbleViewController and BubbleView stubs.

ios/chrome/browser/ui/bubble_promo/bubble_view_controller.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/chrome/browser/ui/bubble_promo/bubble_view_controller.h"
+
+#if !defined(__has_feature) || !__has_feature(objc_arc)
+#error "This file requires ARC support."
+#endif
+
+@implementation BubbleViewController
+
+@synthesize bubbleOrigin = _bubbleOrigin;
+
+- (instancetype)initWithConfiguration:(BubbleConfiguration*)configuration {
+  self = [super initWithNibName:nil bundle:nil];
+  return self;
+}
+
+- (void)animateContentIn {
+}
+
+- (void)dismissAnimated:(BOOL)animated {
+}
+
+// Calculate the bubble's desired origin based on label size, alignment, arrow
+// direction, and the frame of the target UI element.
+- (CGPoint)bubbleOrigin {
+  return _bubbleOrigin;
+}
+
+@end