Merge HlsParserUtil into HlsPlaylistParser

It's the only place that uses it.

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=127927164

library/src/main/java/com/google/android/exoplayer2/source/hls/playlist/HlsParserUtil.java

-/*
- * Copyright (C) 2016 The Android Open Source Project
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *      http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-package com.google.android.exoplayer2.source.hls.playlist;
-
-import com.google.android.exoplayer2.ParserException;
-
-import java.util.regex.Matcher;
-import java.util.regex.Pattern;
-
-/**
- * Utility methods for HLS manifest parsing.
- */
-/* package */ final class HlsParserUtil {
-
-  private static final String BOOLEAN_TRUE_VALUE = "YES";
-  private static final String BOOLEAN_FALSE_VALUE = "NO";
-
-  private HlsParserUtil() {}
-
-  public static String parseStringAttr(String line, Pattern pattern, String tag)
-      throws ParserException {
-    Matcher matcher = pattern.matcher(line);
-    if (matcher.find() && matcher.groupCount() == 1) {
-      return matcher.group(1);
-    }
-    throw new ParserException("Couldn't match " + tag + " tag in " + line);
-  }
-
-  public static int parseIntAttr(String line, Pattern pattern, String tag)
-      throws ParserException {
-    return Integer.parseInt(parseStringAttr(line, pattern, tag));
-  }
-
-  public static double parseDoubleAttr(String line, Pattern pattern, String tag)
-      throws ParserException {
-    return Double.parseDouble(parseStringAttr(line, pattern, tag));
-  }
-
-  public static String parseOptionalStringAttr(String line, Pattern pattern) {
-    Matcher matcher = pattern.matcher(line);
-    if (matcher.find()) {
-      return matcher.group(1);
-    }
-    return null;
-  }
-
-  public static boolean parseBooleanAttribute(String line, Pattern pattern, boolean defaultValue) {
-    Matcher matcher = pattern.matcher(line);
-    if (matcher.find()) {
-      return matcher.group(1).equals(BOOLEAN_TRUE_VALUE);
-    }
-    return defaultValue;
-  }
-
-  public static Pattern compileBooleanAttrPattern(String attribute) {
-    return Pattern.compile(attribute + "=(" + BOOLEAN_FALSE_VALUE + "|" + BOOLEAN_TRUE_VALUE + ")");
-
-  }
-
-}