[evolution] Fix a compiler warning (maybe-uninitialized)

[Milan Crha <mcrha src gnome org>]

commit cc9e66b8a70bb4e81b9ab2ed227b7b81b859258d
Author: Milan Crha <mcrha redhat com>
Date:   Fri Mar 24 15:07:06 2017 +0100

    Fix a compiler warning (maybe-uninitialized)

 .../web-extension/e-editor-dom-functions.c         |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/src/modules/webkit-editor/web-extension/e-editor-dom-functions.c 
b/src/modules/webkit-editor/web-extension/e-editor-dom-functions.c
index c1e01e0..51cfc41 100644
--- a/src/modules/webkit-editor/web-extension/e-editor-dom-functions.c
+++ b/src/modules/webkit-editor/web-extension/e-editor-dom-functions.c
@@ -5803,7 +5803,7 @@ body_drop_event_cb (WebKitDOMElement *element,
 
        if (e_editor_page_is_pasting_content_from_itself (editor_page)) {
                EEditorUndoRedoManager *manager;
-               EEditorHistoryEvent *and_event, *event;
+               EEditorHistoryEvent *and_event, *event = NULL;
 
                /* There is a weird thing going on and I still don't know if it's
                 * caused by WebKit or Evolution. If dragging content around the