Suppress Autofill popup if it would be outside the viewport.

chrome/browser/ui/autofill/chrome_autofill_client.cc

 // Copyright 2014 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.
 
 #include "chrome/browser/ui/autofill/chrome_autofill_client.h"
 
 #include <utility>
 
 #include "base/bind.h"
 #include "base/command_line.h"
@@ skipping 235 matching lines @@
   CreditCardScannerController::ScanCreditCard(web_contents(), callback);
 }
 
 void ChromeAutofillClient::ShowAutofillPopup(
     const gfx::RectF& element_bounds,
     base::i18n::TextDirection text_direction,
     const std::vector<autofill::Suggestion>& suggestions,
     base::WeakPtr<AutofillPopupDelegate> delegate) {
   // Convert element_bounds to be in screen space.
   gfx::Rect client_area = web_contents()->GetContainerBounds();
+
+  // Element bounds are relative to the viewport (client_area).
+  if ((element_bounds.y() + element_bounds.height()) < 0 ||

[Evan Stade, 2017/01/18 00:05:46]

nit: element_bounds.bottom()

[lgarron, 2017/04/05 00:59:42]

Ooh, good to know.

+      (element_bounds.y() + element_bounds.height()) >= client_area.height()) {

[Evan Stade, 2017/01/18 00:05:46]

what about the x direction? Seems like this should be something like

if (!gfx::Rect(client_area.size()).Contains(element_bounds))

[lgarron, 2017/04/05 00:59:43]

Oh, right. I explicitly discussed this with estark@, then promptly forgot to put
it in the code. :-(

Anyhow, your code doesn't work as-is because of Rect/RectF incompatibility, but
that made me realize that it's cleaner to do the calculations using screen
coordinates right after calculating element_bounds_in_screen_space.

+    // The top of the popup would be outside the viewport (and would disappear
+    // before the relevant field can scroll into the viewport), so we supress

[Evan Stade, 2017/01/18 00:05:46]

nit: suppress

[lgarron, 2017/04/05 00:59:41]

Done.

+    // it to avoid crbug.com/678713
+    return;
+  }
+
   gfx::RectF element_bounds_in_screen_space =
       element_bounds + client_area.OffsetFromOrigin();
 
   // Will delete or reuse the old |popup_controller_|.
   popup_controller_ =
       AutofillPopupControllerImpl::GetOrCreate(popup_controller_,
                                                delegate,
                                                web_contents(),
                                                web_contents()->GetNativeView(),
                                                element_bounds_in_screen_space,
@@ skipping 129 matching lines @@
 }
 
 void ChromeAutofillClient::ShowHttpNotSecureExplanation() {
   web_contents()->OpenURL(content::OpenURLParams(
       GURL(kSecurityIndicatorHelpCenterUrl), content::Referrer(),
       WindowOpenDisposition::NEW_FOREGROUND_TAB, ui::PAGE_TRANSITION_LINK,
       false /* is_renderer_initiated */));
 }
 
 }  // namespace autofill