Make ChromeAutofillClient a ZoomObserver.

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 d848917132c9be6350cbc02e862f67818941a729..c3d985a994d60bfff8950e15cdf29f785ba2d38e 100644
--- a/chrome/browser/ui/autofill/chrome_autofill_client.cc
+++ b/chrome/browser/ui/autofill/chrome_autofill_client.cc
@@ -37,6 +37,11 @@ namespace autofill {
 ChromeAutofillClient::ChromeAutofillClient(content::WebContents* web_contents)
     : content::WebContentsObserver(web_contents), web_contents_(web_contents) {
   DCHECK(web_contents);
+  ZoomController* zoom_controller =
+      ZoomController::FromWebContents(web_contents);
+  // No ZoomControllers on Android.
+  if (zoom_controller)
+    zoom_controller->AddObserver(this);
 #if defined(OS_MACOSX) && !defined(OS_IOS)
   RegisterForKeystoneNotifications();
 #endif  // defined(OS_MACOSX) && !defined(OS_IOS)
@@ -172,6 +177,14 @@ void ChromeAutofillClient::WebContentsDestroyed() {
   HideAutofillPopup();
 }
 
+void ChromeAutofillClient::OnZoomChanged(
+    const ZoomController::ZoomChangedEventData& data) {
+  // TODO(wjmaclean) Decide if we want to hide the popup for any zoom event, not
+  // just zoom events for web_contents_.

[Ilya Sherman, 2014/07/09 21:52:43]

What other zoom events are possible?

[wjmaclean, 2014/07/10 14:47:35]

ZoomObservers are notified of the following:
1) changes in zoom level
2) changes in zoom mode (as defined in ZoomController)

(2) & (1) sometimes occur together.

Thinking some more on this, because the ChromeAutofillClient is tied to a single
WebContents, this check will always be true (some ZoomObservers listen to
multiple ZoomControllers, thus the reason the event data carries with
web_contents pointer with it.

+  if (data.web_contents == web_contents_)
+    HideAutofillPopup();
+}
+
 void ChromeAutofillClient::DetectAccountCreationForms(
     const std::vector<autofill::FormStructure*>& forms) {
   password_manager::PasswordGenerationManager* manager =