Reduced skslc memory consumption

src/sksl/SkSLParser.cpp

 /*
  * Copyright 2016 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
  
 #include "stdio.h"
 #include "SkSLParser.h"
 #include "SkSLToken.h"
@@ skipping 139 matching lines @@
 }
 
 Token Parser::nextToken() {
     if (fPushback.fKind != Token::INVALID_TOKEN) {
         Token result = fPushback;
         fPushback.fKind = Token::INVALID_TOKEN;
         fPushback.fText = "";
         return result;
     }
     int token = sksllex(fScanner);
-    return Token(Position(skslget_lineno(fScanner), -1), (Token::Kind) token, 
-                 token == Token::END_OF_FILE ? "<end of file>" : 
-                                               std::string(skslget_text(fScanner)));
+    std::string text;
+    switch ((Token::Kind) token) {
+        case Token::IDENTIFIER:    // fall through
+        case Token::INT_LITERAL:   // fall through
+        case Token::FLOAT_LITERAL: // fall through
+        case Token::DIRECTIVE:
+            text = std::string(skslget_text(fScanner));
+            break;
+        default:
+            break;
+    }
+    return Token(Position(skslget_lineno(fScanner), -1), (Token::Kind) token, text);
 }
 
 void Parser::pushback(Token t) {
     ASSERT(fPushback.fKind == Token::INVALID_TOKEN);
     fPushback = t;
 }
 
 Token Parser::peek() {
     fPushback = this->nextToken();
     return fPushback;
@@ skipping 1305 matching lines @@
 bool Parser::identifier(std::string* dest) {
     Token t;
     if (this->expect(Token::IDENTIFIER, "identifier", &t)) {
         *dest = t.fText; 
         return true;
     }
     return false;
 }
 
 } // namespace