Prevent typing in upload panel

Change-Id: I4de309c15fa25388b2842d5e101ee0b83e439104
Signed-off-by: Edwin Kempin <edwin.kempin@sap.com>

src/main/java/com/googlesource/gerrit/plugins/imagare/client/UploadByDropOrPastePanel.java

diff --git a/src/main/java/com/googlesource/gerrit/plugins/imagare/client/UploadByDropOrPastePanel.java b/src/main/java/com/googlesource/gerrit/plugins/imagare/client/UploadByDropOrPastePanel.java
index e521b20..e034e69 100644
--- a/src/main/java/com/googlesource/gerrit/plugins/imagare/client/UploadByDropOrPastePanel.java
+++ b/src/main/java/com/googlesource/gerrit/plugins/imagare/client/UploadByDropOrPastePanel.java
@@ -27,6 +27,7 @@
     getElement().setAttribute("contenteditable", "true");
     getElement().setAttribute("onpaste", "imagarePasteHandler(this, event)");
     getElement().setAttribute("ondrop", "imagareDropHandler(this, event)");
+    getElement().setAttribute("onkeypress", "imagarePreventKeyPress(event)");
 
     add(new Label("drag and drop image here"));
     add(new Label("or"));
@@ -38,6 +39,14 @@
   }-*/;
 
   private static native void init0() /*-{
+    $wnd.imagarePreventKeyPress = function preventKeys(event) {
+      event = event || window.event;
+      var ctrlDown = event.ctrlKey || event.metaKey;
+      if (!ctrlDown) {
+        event.preventDefault();
+      }
+    }
+
     $wnd.imagarePasteHandler = function handlePaste(elem, e) {
       var savedContent = elem.innerHTML;