Suppress Autofill popup if it would be outside the viewport.

chrome/browser/ui/autofill/chrome_autofill_client.cc

Index: chrome/browser/ui/autofill/chrome_autofill_client.cc
diff --git a/chrome/browser/ui/autofill/chrome_autofill_client.cc b/chrome/browser/ui/autofill/chrome_autofill_client.cc
index 6b85038c7ef3f6ec306378270330550825c2d9fc..01583c02de0ee00cb0466c8dfcb7cfd12079e669 100644
--- a/chrome/browser/ui/autofill/chrome_autofill_client.cc
+++ b/chrome/browser/ui/autofill/chrome_autofill_client.cc
@@ -253,6 +253,16 @@ void ChromeAutofillClient::ShowAutofillPopup(
     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();