Bug 81572: "Never provide only a text field for file/folder input (newsrc file)"

r=mscott, sr=bienvenu

mailnews/base/prefs/resources/content/am-server.js

@@ -273,3 +273,30 @@ function setupNotifyUI()
     if (locked)
       broadcaster.setAttribute("disabled","true");
 }
+
+function BrowseForNewsrc()
+{
+  var newsrcTextBox = document.getElementById("nntp.newsrcFilePath");
+  var fp = Components.classes["@mozilla.org/filepicker;1"].createInstance(nsIFilePicker);
+  fp.init(window, 
+          document.getElementById("browseForNewsrc").getAttribute("filepickertitle"),
+          nsIFilePicker.modeSave);
+
+  var currentNewsrcFile;
+  try {
+    currentNewsrcFile = Components.classes[LOCALFILE_CTRID].createInstance(nsILocalFile);
+    currentNewsrcFile.initWithPath(newsrcTextBox.value);
+  } catch (e) {
+    dump("Failed to create nsILocalFile instance for the current newsrc file.\n");
+  }
+
+  if (currentNewsrcFile) {
+    fp.displayDirectory = currentNewsrcFile.parent;
+    fp.defaultString = currentNewsrcFile.leafName;
+  }
+
+  fp.appendFilters(nsIFilePicker.filterAll);
+
+  if (fp.show() != nsIFilePicker.returnCancel)
+    newsrcTextBox.value = fp.file.path;
+}

mailnews/base/prefs/resources/content/am-server.xul

@@ -269,9 +269,13 @@
   <vbox hidefor="imap,pop3,movemail">
     <label value="&newsrcFilePath.label;" control="nntp.newsrcFilePath"
            accesskey="&newsrcFilePath.accesskey;"/>
-    <textbox wsm_persist="true" id="nntp.newsrcFilePath"
+    <hbox align="center">
+      <textbox readonly="true" wsm_persist="true" flex="1" id="nntp.newsrcFilePath"
                datatype="nsIFileSpec"
                prefstring="mail.server.%serverkey%.newsrc.file" class="uri-element"/>
+      <button id="browseForNewsrc" label="&browseNewsrc.label;" filepickertitle="&newsrcPicker.label;"
+              accesskey="&browseNewsrc.accesskey;" oncommand="BrowseForNewsrc()"/>
+    </hbox>
   </vbox>
 
   </vbox>

mailnews/base/prefs/resources/locale/en-US/am-server-top.dtd

@@ -76,3 +76,6 @@
 <!ENTITY localFolderPicker.label "Select Local Directory">
 <!ENTITY browseFolder.label "Browse...">
 <!ENTITY browseFolder.accesskey "B">
+<!ENTITY newsrcPicker.label "Select newsrc File">
+<!ENTITY browseNewsrc.label "Browse...">
+<!ENTITY browseNewsrc.accesskey "e">