Add "previewing on hover" support for password field.

components/password_manager/core/browser/password_manager_driver.h

Index: components/password_manager/core/browser/password_manager_driver.h
diff --git a/components/password_manager/core/browser/password_manager_driver.h b/components/password_manager/core/browser/password_manager_driver.h
index 8087af7a9367aa78460eb6c80ad753bb35c98984..516bb26867704718a04969d58b1ac88561c84e20 100644
--- a/components/password_manager/core/browser/password_manager_driver.h
+++ b/components/password_manager/core/browser/password_manager_driver.h
@@ -45,11 +45,17 @@ class PasswordManagerDriver {
   virtual void AccountCreationFormsFound(
       const std::vector<autofill::FormData>& forms) = 0;
 
-  // Tells the driver to accept the password autofill suggestion for |username|
-  // and fill the password with |password|.
-  virtual void AcceptPasswordAutofillSuggestion(
-      const base::string16& username,
-      const base::string16& password) = 0;
+  // Tells the driver to fill the form with the |username| and |password|.
+  virtual void FillSuggestion(const base::string16& username,
+                              const base::string16& password) = 0;
+
+  // Tells the driver to preview filling form with the |username| and
+  // password|.

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

nit: missing an '|' before "password|".

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

Done.

+  virtual void PreviewSuggestion(const base::string16& username,
+                                 const base::string16& password) = 0;
+
+  // Clear previewed password and username fields.

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

nit: "Tells the driver to clear ..."

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

Done.

+  virtual void ClearPreviewedForm() = 0;
 
   // Returns the PasswordGenerationManager associated with this instance.
   virtual PasswordGenerationManager* GetPasswordGenerationManager() = 0;