Add a flag to enable/disable the diskstats logging service.

Bug: 34704947
Test: Service tests
Change-Id: I224cfb38682f1fd2bd33750b664bd3aacdaa4bde
diff --git a/services/core/java/com/android/server/storage/DiskStatsLoggingService.java b/services/core/java/com/android/server/storage/DiskStatsLoggingService.java
index 0a3abf3..7c43162 100644
--- a/services/core/java/com/android/server/storage/DiskStatsLoggingService.java
+++ b/services/core/java/com/android/server/storage/DiskStatsLoggingService.java
@@ -21,6 +21,7 @@
 import android.app.job.JobScheduler;
 import android.app.job.JobService;
 import android.content.ComponentName;
+import android.content.ContentResolver;
 import android.content.Context;
 import android.content.pm.PackageStats;
 import android.os.AsyncTask;
@@ -28,6 +29,7 @@
 import android.os.Environment;
 import android.os.Environment.UserEnvironment;
 import android.os.UserHandle;
+import android.provider.Settings;
 import android.util.Log;
 
 import com.android.internal.annotations.VisibleForTesting;
@@ -54,7 +56,7 @@
     public boolean onStartJob(JobParameters params) {
         // We need to check the preconditions again because they may not be enforced for
         // subsequent runs.
-        if (!isCharging(this)) {
+        if (!isCharging(this) || !isDumpsysTaskEnabled(getContentResolver())) {
             jobFinished(params, true);
             return false;
         }
@@ -105,6 +107,12 @@
     }
 
     @VisibleForTesting
+    static boolean isDumpsysTaskEnabled(ContentResolver resolver) {
+        // The default is to treat the task as enabled.
+        return Settings.Global.getInt(resolver, Settings.Global.ENABLE_DISKSTATS_LOGGING, 1) != 0;
+    }
+
+    @VisibleForTesting
     static class LogRunnable implements Runnable {
         private static final long TIMEOUT_MILLIS = TimeUnit.MINUTES.toMillis(10);