Revert 86246 - Fix assertion failure in range.mm while examining system dictionary popup.

chrome/browser/renderer_host/text_input_client_message_filter.mm

Index: chrome/browser/renderer_host/text_input_client_message_filter.mm
===================================================================
--- chrome/browser/renderer_host/text_input_client_message_filter.mm	(revision 86247)
+++ chrome/browser/renderer_host/text_input_client_message_filter.mm	(working copy)
@@ -43,11 +43,6 @@
 
 void TextInputClientMessageFilter::OnGotCharacterIndexForPoint(size_t index) {
   TextInputClientMac* service = TextInputClientMac::GetInstance();
-  // |index| could be WTF::notFound (-1) and it's value is different from
-  // NSNotFound so we need to convert it.
-  if (index == static_cast<size_t>(-1)) {
-    index = NSNotFound;
-  }
   service->SetCharacterIndexAndSignal(index);
 }