mandoline: Add find in page.

components/web_view/public/interfaces/web_view.mojom

Index: components/web_view/public/interfaces/web_view.mojom
diff --git a/components/web_view/public/interfaces/web_view.mojom b/components/web_view/public/interfaces/web_view.mojom
index 1385b8de2d50b4a047e1a6cc2a102108516132e8..2f2f686b7bcc13d01fdeff37c160d5365431fb8a 100644
--- a/components/web_view/public/interfaces/web_view.mojom
+++ b/components/web_view/public/interfaces/web_view.mojom
@@ -27,6 +27,13 @@ interface WebViewClient {
 
   // TODO(beng): also forward text direction.
   TitleChanged(string? title);
+
+  // Reports the number of matches for a given Find() call.
+  ReportFindInPageMatchCount(int32 request_id, int32 count, bool final_update);

[sky, 2015/10/05 15:55:08]

Why the Report? Maybe FindInPatchMatchCountUpdated and
FindInPageSelectionUpdated.

+
+  // Reports which find match is selected. (If there are five highlighted
+  // matches on a page, and the 2nd is selected, |active_match_ordinal| is 2.)
+  ReportFindInPageSelection(int32 request_id, int32 active_match_ordinal);
 };
 
 interface WebView {
@@ -36,6 +43,10 @@ interface WebView {
   // Provide a ViewTreeClient for this specific WebView.
   GetViewTreeClient(mojo.ViewTreeClient& view_tree_client);
 
+  // Finds a string in page.

[sky, 2015/10/05 15:55:08]

Document what request_id is and any restrictions on it. Also, document what this
results in calling on WebViewClient.

+  Find(int32 request_id, string search_text);
+  StopFinding();
+  
   // Moves forward and backward.
   GoBack();
   GoForward();