Revert "Remove StrictMode warnings."

This reverts commit f3e8d033cc.

src/main/java/de/dennisguse/opentracks/Startup.java

@@ -4,6 +4,7 @@ import android.annotation.SuppressLint;
 import android.app.Application;
 import android.content.Context;
 import android.os.Build;
+import android.os.StrictMode;
 import android.util.Log;
 
 import java.lang.reflect.Method;
@@ -27,6 +28,11 @@ public class Startup extends Application {
 
         // Include version information into stack traces.
         Log.i(TAG, BuildConfig.APPLICATION_ID + "; BuildType: " + BuildConfig.BUILD_TYPE + "; VersionName: " + BuildConfig.VERSION_NAME + "/" + BuildConfig.VERSION_NAME_FULL + " VersionCode: " + BuildConfig.VERSION_CODE);
+        // In debug builds: show thread and VM warnings.
+        if (BuildConfig.DEBUG) {
+            Log.d(TAG, "Enabling strict mode");
+            StrictMode.enableDefaults();
+        }
 
         PreferencesUtils.initPreferences(this);
         // Set default values of preferences on first start.