Rescue and re-raise syntax errors in Template#parse to add line numbers.

This can be done now that the parse context has the line number
information, so it doesn't need to be added on closer to the original
exception.  This has the advantage of not having to rescue and re-raise the
exception multiple times, and simplifies liquid-c which would otherwise
have to rescue the exception in BlockBody#parse.

lib/liquid/block_body.rb

@@ -15,7 +15,6 @@ module Liquid
     def parse(tokenizer, parse_context)
       parse_context.line_number = tokenizer.line_number
       while token = tokenizer.shift
-        begin
         unless token.empty?
           case
           when token.start_with?(TAGSTART)
@@ -43,10 +42,6 @@ module Liquid
             @blank &&= !!(token =~ /\A\s*\z/)
           end
         end
-        rescue SyntaxError => e
-          e.line_number ||= parse_context.line_number
-          raise
-        end
         parse_context.line_number = tokenizer.line_number
       end
 

lib/liquid/parser_switching.rb

@@ -8,7 +8,6 @@ module Liquid
         begin
           return strict_parse_with_error_context(markup)
         rescue SyntaxError => e
-          e.line_number = line_number
           @options.warnings << e
           return lax_parse(markup)
         end
@@ -20,6 +19,7 @@ module Liquid
     def strict_parse_with_error_context(markup)
       strict_parse(markup)
     rescue SyntaxError => e
+      e.line_number = line_number
       e.markup_context = markup_context(markup)
       raise e
     end

lib/liquid/template.rb

@@ -120,6 +120,9 @@ module Liquid
       @root = Document.parse(tokenize(source), parse_context)
       @warnings = parse_context.warnings
       self
+    rescue SyntaxError => e
+      e.line_number ||= parse_context.line_number
+      raise
     end
 
     def registers