Add "previewing on hover" support for single-field autocomplete input

components/autofill/core/browser/autofill_driver.h

Index: components/autofill/core/browser/autofill_driver.h
diff --git a/components/autofill/core/browser/autofill_driver.h b/components/autofill/core/browser/autofill_driver.h
index 933ef689b3f80fd0a5d7d523416c76f6a73155a1..8d906c58b971f6c48be017eb9f9ecbe3652630fd 100644
--- a/components/autofill/core/browser/autofill_driver.h
+++ b/components/autofill/core/browser/autofill_driver.h
@@ -81,6 +81,10 @@ class AutofillDriver {
   // Tells the renderer to clear the currently previewed Autofill results.
   virtual void RendererShouldClearPreviewedForm() = 0;
 
+  // Tells the renderer to preview the AutoComplete node.
+  virtual void RendererShouldPreviewAutoCompleteNode(
+      const base::string16& value) = 0;

[Ilya Sherman, 2014/02/22 05:59:51]

nit: Please move this to be below the corresponding method for filling the
field.  I'd like to consistently order methods as "fill" followed by "preview".

[ziran.sun, 2014/02/27 15:38:11]

Done.

+
   // Tells the renderer to set the node text.
   virtual void RendererShouldSetNodeText(const base::string16& value) = 0;
 };