In processEs6Modules(), don't trigger ES6 module detection / line-based parsing if no dependency would be pruned
In this case, all files will be fully parsed anyway so don't do the extra work of line-based parsing.
@@ -1882,6 +1882,7 @@ public class Compiler extends AbstractCompiler implements ErrorHandler, SourceFi
for (CompilerInput input : inputsToProcess) {
// Only process files that are detected as ES6 modules or forced to be rewritten
if (forceRewrite
+ || !options.dependencyOptions.shouldPruneDependencies()
|| !JsFileParser.isSupported()
|| (input.getLoadFlags().containsKey("module")
&& input.getLoadFlags().get("module").equals("es6"))) {
