fix activity leak when initializing singletons

Closes #3219
// FREEBIE

src/org/thoughtcrime/securesms/database/CanonicalAddressDatabase.java

@@ -56,7 +56,7 @@ public class CanonicalAddressDatabase {
   public static CanonicalAddressDatabase getInstance(Context context) {
     synchronized (lock) {
       if (instance == null)
-        instance = new CanonicalAddressDatabase(context);
+        instance = new CanonicalAddressDatabase(context.getApplicationContext());
 
       return instance;
     }
@@ -69,7 +69,7 @@ public class CanonicalAddressDatabase {
 
   public void reset(Context context) {
     DatabaseHelper old  = this.databaseHelper;
-    this.databaseHelper = new DatabaseHelper(context, DATABASE_NAME, null, DATABASE_VERSION);
+    this.databaseHelper = new DatabaseHelper(context.getApplicationContext(), DATABASE_NAME, null, DATABASE_VERSION);
     old.close();
     fillCache();
   }

src/org/thoughtcrime/securesms/database/DatabaseFactory.java

@@ -85,7 +85,7 @@ public class DatabaseFactory {
   public static DatabaseFactory getInstance(Context context) {
     synchronized (lock) {
       if (instance == null)
-        instance = new DatabaseFactory(context);
+        instance = new DatabaseFactory(context.getApplicationContext());
 
       return instance;
     }