Improved the warning icon: Higher resolution, better size.

res/layout/conversation_item_received.xml

@@ -157,7 +157,7 @@
             <ImageView android:id="@+id/sms_failed_indicator"
                 android:layout_width="wrap_content"
                 android:layout_height="wrap_content"
-                android:src="@drawable/ic_list_alert_sms_failed"
+                android:src="@drawable/ic_action_warning_red"
                 android:contentDescription="@string/conversation_item_sent__send_failed_indicator_description"
                 android:visibility="gone" />
         </LinearLayout>

res/layout/conversation_item_sent.xml

@@ -27,7 +27,7 @@
                 android:id="@+id/sms_failed_indicator"
                 android:layout_width="wrap_content"
                 android:layout_height="wrap_content"
-                android:src="@drawable/ic_list_alert_sms_failed"
+                android:src="@drawable/ic_action_warning_red"
                 android:visibility="gone"
                 android:contentDescription="@string/conversation_item_sent__send_failed_indicator_description"/>
 

res/layout/conversation_list_item_view.xml

@@ -67,7 +67,7 @@
                        android:layout_height="match_parent"
                        android:layout_width="20sp"
                        android:visibility="gone"
-                       android:src="@drawable/ic_list_alert_sms_failed"
+                       android:src="@drawable/ic_action_warning_red"
                        android:contentDescription="Error Alert" />
 
             <TextView android:id="@+id/date"