Add "previewing on hover" support for password field.

components/password_manager/core/browser/password_autofill_manager.cc

Index: components/password_manager/core/browser/password_autofill_manager.cc
diff --git a/components/password_manager/core/browser/password_autofill_manager.cc b/components/password_manager/core/browser/password_autofill_manager.cc
index 8ace098c8aadbe134c461bc371c527b0fb98cc5e..36108a0598abf90c1a11af6745130076b55e33c7 100644
--- a/components/password_manager/core/browser/password_autofill_manager.cc
+++ b/components/password_manager/core/browser/password_autofill_manager.cc
@@ -40,6 +40,20 @@ bool PasswordAutofillManager::AcceptSuggestion(
   return false;
 }
 
+bool PasswordAutofillManager::SelectSuggestion(
+    const autofill::FormFieldData& field,
+    const base::string16& username) {
+  autofill::PasswordFormFillData fill_data;
+  base::string16 password;
+  if (FindLoginInfo(field, &fill_data) &&
+      GetPasswordForUsername(username, fill_data, &password)) {
+    PasswordManagerDriver* driver = password_manager_client_->GetDriver();
+    driver->PreviewPasswordAutofillSuggestion(username, password);
+    return true;
+  }
+  return false;
+}
+
 void PasswordAutofillManager::OnAddPasswordFormMapping(
     const autofill::FormFieldData& field,
     const autofill::PasswordFormFillData& fill_data) {
@@ -90,6 +104,12 @@ bool PasswordAutofillManager::AcceptSuggestionForTest(
   return AcceptSuggestion(field, username);
 }
 
+bool PasswordAutofillManager::SelectSuggestionForTest(
+    const autofill::FormFieldData& field,
+    const base::string16& username) {
+  return SelectSuggestion(field, username);
+}
+
 void PasswordAutofillManager::OnPopupShown() {
 }
 
@@ -98,9 +118,9 @@ void PasswordAutofillManager::OnPopupHidden() {
 
 void PasswordAutofillManager::DidSelectSuggestion(const base::string16& value,
                                                   int identifier) {
-  // This is called to preview an autofill suggestion, but we don't currently
-  // do that for password forms (crbug.com/63421). If it is ever implemented,
-  // ClearPreviewedForm() must also be implemented().
+  ClearPreviewedForm();
+  if (!SelectSuggestion(form_field_, value))
+    NOTREACHED();

[Ilya Sherman, 2014/05/13 00:44:05]

nit: Please write these two lines as

bool success = SelectSuggestion(form_field_, value);
DCHECK(success);

[ziran.sun, 2014/05/14 15:35:12]

What about NOTREACHED() uses in other places of this file? Does it make sense to
replace them with DCHECK as well?

[Ilya Sherman, 2014/05/14 23:10:58]

Yes, let's do that :)

[ziran.sun, 2014/05/15 12:36:37]

Done.

 }
 
 void PasswordAutofillManager::DidAcceptSuggestion(const base::string16& value,
@@ -116,8 +136,8 @@ void PasswordAutofillManager::RemoveSuggestion(const base::string16& value,
 }
 
 void PasswordAutofillManager::ClearPreviewedForm() {
-  // There is currently no preview for password autofill (crbug.com/63421).
-  // This function needs an implemention if preview is ever implemented.
+  PasswordManagerDriver* driver = password_manager_client_->GetDriver();
+  driver->ClearPasswordPreviewedForm();
 }
 
 ////////////////////////////////////////////////////////////////////////////////