Remove sarcastic error message.

This is not helpful.

Change-Id: I4a25268e83209db3a4b5d3dcb4a93940340de343
Reviewed-on: https://gn-review.googlesource.com/2620
Reviewed-by: Julie Hockett <juliehockett@google.com>
Commit-Queue: Brett Wilson <brettw@chromium.org>

tools/gn/tokenizer.cc

diff --git a/tools/gn/tokenizer.cc b/tools/gn/tokenizer.cc
index b596c74..9625203 100644
--- a/tools/gn/tokenizer.cc
+++ b/tools/gn/tokenizer.cc
@@ -259,8 +259,7 @@
         char c = cur_char();
         if (!IsCurrentWhitespace() && !CouldBeOperator(c) && !IsScoperChar(c) &&
             c != ',') {
-          *err_ = Err(GetCurrentLocation(), "This is not a valid number.",
-                      "Learn to count.");
+          *err_ = Err(GetCurrentLocation(), "This is not a valid number.");
           // Highlight the number.
           err_->AppendRange(LocationRange(location, GetCurrentLocation()));
         }