Implement WebViewDatabase's hasFormData API for chromium based webview.

components/autofill/browser/webdata/autofill_webdata_backend.cc

 // Copyright (c) 2012 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 "components/autofill/browser/webdata/autofill_webdata_backend.h"
 
 #include "base/logging.h"
 #include "base/stl_util.h"
 #include "components/autofill/browser/autofill_country.h"
 #include "components/autofill/browser/autofill_profile.h"
@@ skipping 54 matching lines @@
     WebDatabase* db) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::DB));
   std::vector<base::string16> values;
   AutofillTable::FromWebDatabase(db)->GetFormValuesForElementName(
       name, prefix, &values, limit);
   return scoped_ptr<WDTypedResult>(
       new WDResult<std::vector<base::string16> >(AUTOFILL_VALUE_RESULT,
                                                  values));
 }
 
+scoped_ptr<WDTypedResult> AutofillWebDataBackend::HasFormElements(
+    WebDatabase* db) {
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::DB));
+  bool value = AutofillTable::FromWebDatabase(db)->HasFormElements();
+  return scoped_ptr<WDTypedResult>(
+      new WDResult<bool>(AUTOFILL_VALUE_RESULT, value));
+}
+
 WebDatabase::State AutofillWebDataBackend::RemoveFormElementsAddedBetween(
     const base::Time& delete_begin, const base::Time& delete_end,
     WebDatabase* db) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::DB));
   AutofillChangeList changes;
 
   if (AutofillTable::FromWebDatabase(db)->RemoveFormElementsAddedBetween(
       delete_begin, delete_end, &changes)) {
     if (!changes.empty()) {
       // Post the notifications including the list of affected keys.
@@ skipping 223 matching lines @@
       const WDTypedResult* result) {
   DCHECK(result->GetType() == AUTOFILL_CREDITCARDS_RESULT);
   const WDResult<std::vector<CreditCard*> >* r =
       static_cast<const WDResult<std::vector<CreditCard*> >*>(result);
 
   std::vector<CreditCard*> credit_cards = r->GetValue();
   STLDeleteElements(&credit_cards);
 }
 
 }  // namespace autofill