Remove Instant v1 API.

chrome/browser/instant/instant_commit_type.h

Index: chrome/browser/instant/instant_commit_type.h
diff --git a/chrome/browser/instant/instant_commit_type.h b/chrome/browser/instant/instant_commit_type.h
index 980670de3c0b76b6982fa0553583f60ec1cf1b34..dfefcf656d334e9f679c07a08b6fdd3634290434 100644
--- a/chrome/browser/instant/instant_commit_type.h
+++ b/chrome/browser/instant/instant_commit_type.h
@@ -7,15 +7,12 @@
 
 // Reason why the Instant preview is committed (merged into a tab).
 enum InstantCommitType {
-  // The commit is due to the user pressing enter or tab from the omnibox.
+  // The commit is due to the user pressing Enter from the omnibox.
   INSTANT_COMMIT_PRESSED_ENTER,
 
   // The commit is due to the omnibox losing focus, usually due to the user
   // clicking on the preview.
   INSTANT_COMMIT_FOCUS_LOST,
-
-  // Used internally by InstantController.
-  INSTANT_COMMIT_DESTROY
 };
 
 #endif  // CHROME_BROWSER_INSTANT_INSTANT_COMMIT_TYPE_H_