Add "previewing on hover" support for password field.

components/autofill/content/browser/content_autofill_driver_unittest.cc

Index: components/autofill/content/browser/content_autofill_driver_unittest.cc
diff --git a/components/autofill/content/browser/content_autofill_driver_unittest.cc b/components/autofill/content/browser/content_autofill_driver_unittest.cc
index edb4aa0e94f27830555fd84f6caf879283976213..3618587db0bd7dbe0876d9abea22ff3bae937e00 100644
--- a/components/autofill/content/browser/content_autofill_driver_unittest.cc
+++ b/components/autofill/content/browser/content_autofill_driver_unittest.cc
@@ -165,6 +165,10 @@ class ContentAutofillDriverTest : public ChromeRenderViewHostTestHarness {
         if (!AutofillMsg_PreviewFieldWithValue::Read(message, &autofill_param))
           return false;
         break;
+      case AutofillMsg_PreviewPassword::ID:
+        if (!AutofillMsg_PreviewPassword::Read(message, &autofill_param))
+          return false;
+        break;
       case AutofillMsg_AcceptDataListSuggestion::ID:
         if (!AutofillMsg_AcceptDataListSuggestion::Read(message,
                                                         &autofill_param))
@@ -334,4 +338,13 @@ TEST_F(ContentAutofillDriverTest, PreviewFieldWithValue) {
   EXPECT_EQ(input_value, output_value);
 }
 
+TEST_F(ContentAutofillDriverTest, PreviewPassword) {
+  base::string16 input_value(base::ASCIIToUTF16("barqux"));
+  base::string16 output_value;
+  driver_->RendererShouldPreviewPassword(input_value);
+  EXPECT_TRUE(GetString16FromMessageWithID(
+      AutofillMsg_PreviewPassword::ID, &output_value));
+  EXPECT_EQ(input_value, output_value);
+}
+
 }  // namespace autofill