Omnibox: Add logging of what type of page was displayed when it's used

chrome/common/metrics/proto/omnibox_event.proto

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 //
 // Stores information about an omnibox interaction.
 
 syntax = "proto2";
 
 option optimize_for = LITE_RUNTIME;
 
 package metrics;
 
-// Next tag: 10
+// Next tag: 11
 message OmniboxEventProto {
   // The timestamp for the event, in seconds since the epoch.
   optional int64 time = 1;
 
   // The id of the originating tab for this omnibox interaction.
   // This is the current tab *unless* the user opened the target in a new tab.
   // In those cases, this is unset.  Tab ids are unique for a given session_id
   // (in the containing protocol buffer ChromeUserMetricsExtensionsProto).
   optional int32 tab_id = 2;
 
@@ skipping 12 matching lines @@
   // user-visible text in the omnibox.
   optional int32 completed_length = 6;
 
   // The amount of time, in milliseconds, since the user first began modifying
   // the text in the omnibox.  If at some point after modifying the text, the
   // user reverts the modifications (thus seeing the current web page's URL
   // again), then writes in the omnibox again, this elapsed time should start
   // from the time of the second series of modification.
   optional int64 typing_duration_ms = 7;
 
+  // The type of page currently displayed when the user used the omnibox.
+  enum PageClassification {
+    INVALID_SPEC = 0;   // invalid URI; shouldn't happen
+    NEW_TAB_PAGE = 1;   // chrome://newtab/
+    // Note that chrome://newtab/ doesn't have to be the built-in
+    // version; it could be replaced by an extension.
+    BLANK = 2;          // about:blank
+    HOMEPAGE = 3;       // user switched settings to "open this page" mode.
+    // Note that if the homepage is set to the new tab page or about blank,
+    // then we'll classify the web page into those categories, not HOMEPAGE.
+    OTHER = 4;          // everything else
+  }
+  optional PageClassification current_page_classification = 10;
+
   // What kind of input the user provided.
   enum InputType {
     INVALID = 0;        // Empty input (should not reach here)
     UNKNOWN = 1;        // Valid input whose type cannot be determined
     REQUESTED_URL = 2;  // Input autodetected as UNKNOWN, which the user wants
                         // to treat as an URL by specifying a desired_tld
     URL = 3;            // Input autodetected as a URL
     QUERY = 4;          // Input autodetected as a query
     FORCED_QUERY = 5;   // Input forced to be a query by an initial '?'
   }
@@ skipping 41 matching lines @@
     optional ResultType result_type = 2;
 
     // The relevance score for this suggestion.
     optional int32 relevance = 3;
 
     // Whether this item is starred (bookmarked) or not.
     optional bool is_starred = 4;
   }
   repeated Suggestion suggestion = 9;
 }