[Sync] ApplySyncChanges autofill implementation.

components/autofill/core/browser/webdata/autofill_entry.h

Index: components/autofill/core/browser/webdata/autofill_entry.h
diff --git a/components/autofill/core/browser/webdata/autofill_entry.h b/components/autofill/core/browser/webdata/autofill_entry.h
index 1edc4010dd52bc900d24e6a0c5ea56f66ed608ca..4a934dd4510ecd2aa746240a7003c394dfa588c9 100644
--- a/components/autofill/core/browser/webdata/autofill_entry.h
+++ b/components/autofill/core/browser/webdata/autofill_entry.h
@@ -31,6 +31,7 @@ class AutofillKey {
 
 class AutofillEntry {
  public:
+  AutofillEntry();
   AutofillEntry(const AutofillKey& key,
                 const base::Time& date_created,
                 const base::Time& date_last_used);
@@ -41,6 +42,7 @@ class AutofillEntry {
   const base::Time& date_last_used() const { return date_last_used_; }
 
   bool operator==(const AutofillEntry& entry) const;
+  bool operator!=(const AutofillEntry& entry) const;
   bool operator<(const AutofillEntry& entry) const;
 
  private: