[Mfill Android][Crash Fix] Don't use invalid origins

Before this CL, we would occasionally crash when refreshing suggestions
for a field right after it was unfocused.

To prevent this, we now check that the focus is set and if it isn't, we
use an opaque origin for which we can never have suggestions since it is
a unique Nonce element.

Bug: 957549
Change-Id: I4118b5ea9b7d44416f2f5b3d652cba348487c2df
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1635570
Commit-Queue: Friedrich [CET] <fhorschig@chromium.org>
Reviewed-by: Vasilii Sukhanov <vasilii@chromium.org>
Cr-Commit-Position: refs/heads/master@{#665526}

chrome/browser/password_manager/password_accessory_controller_impl.cc

@@ -186,6 +186,14 @@ void PasswordAccessoryControllerImpl::OnOptionSelected(
 void PasswordAccessoryControllerImpl::RefreshSuggestionsForField(
     FocusedFieldType focused_field_type,
     bool is_manual_generation_available) {
+  // Prevent crashing by not acting at all if frame became unfocused at any
+  // point. The next time a focus event happens, this will be called again and
+  // ensure we show correct data.
+  if (web_contents_->GetFocusedFrame() == nullptr)
+    return;
+  url::Origin origin = GetFocusedFrameOrigin();
+  if (origin.opaque())
+    return;  // Don't proceed for invalid origins.
   std::vector<UserInfo> info_to_add;
   std::vector<FooterCommand> footer_commands_to_add;
 
@@ -219,10 +227,10 @@ void PasswordAccessoryControllerImpl::RefreshSuggestionsForField(
 
   GetManualFillingController()->RefreshSuggestionsForField(
       focused_field_type,
-      autofill::CreateAccessorySheetData(
-          autofill::AccessoryTabType::PASSWORDS,
-          GetTitle(has_suggestions, GetFocusedFrameOrigin()),
-          std::move(info_to_add), std::move(footer_commands_to_add)));
+      autofill::CreateAccessorySheetData(autofill::AccessoryTabType::PASSWORDS,
+                                         GetTitle(has_suggestions, origin),
+                                         std::move(info_to_add),
+                                         std::move(footer_commands_to_add)));
 
   if (is_password_field) {
     GetManualFillingController()->ShowWhenKeyboardIsVisible(
@@ -243,6 +251,8 @@ void PasswordAccessoryControllerImpl::GetFavicon(
     base::OnceCallback<void(const gfx::Image&)> icon_callback) {
   url::Origin origin =
       GetFocusedFrameOrigin();  // Copy origin in case it changes.
+  if (origin.opaque())
+    return;  // Don't proceed for invalid origins.
   // Check whether this request can be immediately answered with a cached icon.
   // It is empty if there wasn't at least one request that found an icon yet.
   FaviconRequestData* icon_request = &icons_request_data_[origin];
@@ -314,6 +324,8 @@ bool PasswordAccessoryControllerImpl::AppearsInSuggestions(
     const base::string16& suggestion,
     bool is_password,
     const url::Origin& origin) const {
+  if (origin.opaque())
+    return false;  // Don't proceed for invalid origins.
   for (const PasswordAccessorySuggestion& element :
        origin_suggestions_.at(origin)) {
     const base::string16& candidate =
@@ -333,6 +345,11 @@ PasswordAccessoryControllerImpl::GetManualFillingController() {
 }
 
 url::Origin PasswordAccessoryControllerImpl::GetFocusedFrameOrigin() const {
+  if (web_contents_->GetFocusedFrame() == nullptr) {
+    LOG(DFATAL) << "Tried to get retrieve origin without focused "
+                   "frame.";
+    return url::Origin();  // Nonce!
+  }
   return web_contents_->GetFocusedFrame()->GetLastCommittedOrigin();
 }