base: remove useless pm cache hack

we anyway made sure cache gets invalidated correctly
does not matter if userdebug eng or whatevber

Change-Id: Idfe319b38d36d56df687a01fb62c468e643a8b60

services/core/java/com/android/server/pm/PackageManagerServiceUtils.java

@@ -1350,7 +1350,7 @@ public static void enforceSystemOrRoot(String message) {
         // NOTE: When no BUILD_NUMBER is set by the build system, it defaults to a build
         // that starts with "eng." to signify that this is an engineering build and not
         // destined for release.
-        if (isUserDebugBuild && incrementalVersion.startsWith("eng.")) {
+        /*if (isUserDebugBuild && incrementalVersion.startsWith("eng.")) {
             // Heuristic: If the /system directory has been modified recently due to an "adb sync"
             // or a regular make, then blow away the cache. Note that mtimes are *NOT* reliable
             // in general and should not be used for production changes. In this specific case,
@@ -1362,7 +1362,7 @@ public static void enforceSystemOrRoot(String message) {
                 FileUtils.deleteContents(cacheBaseDir);
                 cacheDir = FileUtils.createDir(cacheBaseDir, cacheName);
             }
-        }
+        }*/
 
         return cacheDir;
     }