Support @scoped packages when writing perf cache

Summary:Runs mkdirp since scoped packages look like `scope/pkg` which introduce an extra level in the directory hierarchy when creating the filename for the perf cache.

Fixes jestjs#845.
Closes jestjs#846

Differential Revision: D3113637

fb-gh-sync-id: 916cbce81b3eafeebfaf3e7849ab6788b338cea7
fbshipit-source-id: 916cbce81b3eafeebfaf3e7849ab6788b338cea7

Author: ide

src/TestRunner.js

@@ -226,7 +226,7 @@ class TestRunner {
 
   _getTestPerformanceCachePath() {
     const config = this._config;
-    return path.join(config.cacheDirectory, 'perf-cache-' + config.name);
+    return getCacheFilePath(config.cacheDirectory, 'perf-cache-' + config.name);
   }
 
   _sortTests(testPaths) {