Allow sandboxed apps to access only package specific dirs.

Bug: 130427780
Test: manual
Test: atest cts/hostsidetests/appsecurity/src/android/appsecurity/cts/ExternalStorageHostTest.java
Change-Id: I7afcea090306336c4033860084a2a436d2bb4740

VolumeManager.cpp

@@ -119,7 +119,8 @@ VolumeManager::VolumeManager() {
 VolumeManager::~VolumeManager() {}
 
 static bool hasIsolatedStorage() {
-    return GetBoolProperty(kIsolatedStorageSnapshot, GetBoolProperty(kIsolatedStorage, true));
+    return false &&
+           GetBoolProperty(kIsolatedStorageSnapshot, GetBoolProperty(kIsolatedStorage, true));
 }
 
 int VolumeManager::updateVirtualDisk() {
@@ -1098,6 +1099,8 @@ int VolumeManager::remountUidLegacy(uid_t uid, int32_t mountMode) {
             mode = "read";
             break;
         case VoldNativeService::REMOUNT_MODE_WRITE:
+        case VoldNativeService::REMOUNT_MODE_LEGACY:
+        case VoldNativeService::REMOUNT_MODE_INSTALLER:
             mode = "write";
             break;
         default: