Handle File.listFiles() returning null on IO errors

chrome/android/java/src/org/chromium/chrome/browser/share/ShareHelper.java

Index: chrome/android/java/src/org/chromium/chrome/browser/share/ShareHelper.java
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/share/ShareHelper.java b/chrome/android/java/src/org/chromium/chrome/browser/share/ShareHelper.java
index 79ef3a334bb661d51960348702b5927b4ee1a11c..b0d81564b2f7e9807e1603931c6c6f7e6ebc9307 100644
--- a/chrome/android/java/src/org/chromium/chrome/browser/share/ShareHelper.java
+++ b/chrome/android/java/src/org/chromium/chrome/browser/share/ShareHelper.java
@@ -119,7 +119,10 @@ public class ShareHelper {
     private static void deleteShareImageFiles(File file) {
         if (!file.exists()) return;
         if (file.isDirectory()) {
-            for (File f : file.listFiles()) deleteShareImageFiles(f);
+            File[] file_list = file.listFiles();
+            if (file_list != null) {
+                for (File f : file_list) deleteShareImageFiles(f);
+            }
         }
         if (!file.delete()) {
             Log.w(TAG, "Failed to delete share image file: %s", file.getAbsolutePath());