The upgrade to args4j broke parsing of multi-line args. This fix rest…

…ores the behavior.

Closes #2086

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=136370934

src/com/google/javascript/jscomp/CommandLineRunner.java

@@ -1165,7 +1165,7 @@ private static List<String> processArgs(String[] args) {
     // Args4j has a different format that the old command-line parser.
     // So we use some voodoo to get the args into the format that args4j
     // expects.
-    Pattern argPattern = Pattern.compile("(--?[a-zA-Z_]+)=(.*)");
+    Pattern argPattern = Pattern.compile("(--?[a-zA-Z_]+)=(.*)", Pattern.DOTALL);
     Pattern quotesPattern = Pattern.compile("^['\"](.*)['\"]$");
     List<String> processedArgs = new ArrayList<>();