several minor bugs and things listed below

bug:1648729
   print warning if a requery is attemped on main thread
bug:2459293
   browser death because of NoSuchElementException. don't use iterator
   to march thru the ArrayList. use old style for() loop.
bug:1609474
   don't allow downgrades of databases
other stuff
   use LRUcache to maintain statement-cache in SQLiteDatabase
Change-Id: I3a42022162f4dfcc75f7d0cfcad8f20f1d193249

1 files changed, 8 insertions, 4 deletions

diff --git a/core/java/android/database/DataSetObservable.java b/core/java/android/database/DataSetObservable.java
index 9200e8135316..51c72c1877e8 100644
--- a/core/java/android/database/DataSetObservable.java
+++ b/core/java/android/database/DataSetObservable.java
@@ -27,8 +27,12 @@ public class DataSetObservable extends Observable<DataSetObserver> {
      */
     public void notifyChanged() {
         synchronized(mObservers) {
-            for (DataSetObserver observer : mObservers) {
-                observer.onChanged();
+            // since onChanged() is implemented by the app, it could do anything, including
+            // removing itself from {@link mObservers} - and that could cause problems if
+            // an iterator is used on the ArrayList {@link mObservers}.
+            // to avoid such problems, just march thru the list in the reverse order.
+            for (int i = mObservers.size() - 1; i >= 0; i--) {
+                mObservers.get(i).onChanged();
             }
         }
     }
@@ -39,8 +43,8 @@ public class DataSetObservable extends Observable<DataSetObserver> {
      */
     public void notifyInvalidated() {
         synchronized (mObservers) {
-            for (DataSetObserver observer : mObservers) {
-                observer.onInvalidated();
+            for (int i = mObservers.size() - 1; i >= 0; i--) {
+                mObservers.get(i).onInvalidated();
             }
         }
     }