Fix a findbugs error in Addr2LineWorkerPool.java.

Review URL: https://codereview.chromium.org/268533002

git-svn-id: http://src.chromium.org/svn/trunk/src/build@267664 4ff67af0-8c30-449e-8e8b-ad334ec8d88c

android/findbugs_filter/findbugs_known_bugs.txt

@@ -31,4 +31,3 @@ M V MS: org.chromium.content.browser.LoadUrlParams.UA_OVERRIDE_TRUE isn't final
 M M LI: Incorrect lazy initialization of static field org.chromium.chrome.browser.sync.ProfileSyncService.sSyncSetupManager in org.chromium.chrome.browser.sync.ProfileSyncService.get(Context)  At ProfileSyncService.java
 M B OS: org.chromium.tools.binary_size.Addr2LineWorkerPool$Addr2LineWorker$Addr2LineTask.run() may fail to close stream  At Addr2LineWorkerPool.java
 M B RV: Exceptional return value of java.io.File.mkdirs() ignored in new org.chromium.tools.binary_size.NmDumper$Output(NmDumper)  At NmDumper.java
-M D REC: Exception is caught when Exception is not thrown in org.chromium.tools.binary_size.Addr2LineWorkerPool$Addr2LineWorker$Addr2LineTask.run()  At Addr2LineWorkerPool.java