Don't double-count external cached app data.

Cached app data is already counted in extStats.dataSize, so we don't
need to count it twice.

Test: builds, boots, verified Settings UI before/after
Bug: 62343684
Change-Id: Ic02cbe3f5938949730f9bc8d911ed398436f84d7
diff --git a/cmds/installd/InstalldNativeService.cpp b/cmds/installd/InstalldNativeService.cpp
index 3041467..60c89a9 100644
--- a/cmds/installd/InstalldNativeService.cpp
+++ b/cmds/installd/InstalldNativeService.cpp
@@ -1698,7 +1698,7 @@
                 collectQuotaStats(device, userId, appId, nullptr, &extStats);
             }
         }
-        appSize = extStats.dataSize + extStats.cacheSize;
+        appSize = extStats.dataSize;
         ATRACE_END();
     } else {
         ATRACE_BEGIN("manual");