Don't ever set the "base" variable to null.  It is supposed to be the empty string
if it hasn't been set yet.

Review at http://gwt-code-reviews.appspot.com/219801

Review by: jgw@google.com

git-svn-id: https://google-web-toolkit.googlecode.com/svn/trunk@7736 8db76d5a-ed1c-0410-87a9-c151d255dfc7

dev/core/src/com/google/gwt/core/linker/IFrameTemplate.js

diff --git a/dev/core/src/com/google/gwt/core/linker/IFrameTemplate.js b/dev/core/src/com/google/gwt/core/linker/IFrameTemplate.js
index 02d478a..412e049 100644
--- a/dev/core/src/com/google/gwt/core/linker/IFrameTemplate.js
+++ b/dev/core/src/com/google/gwt/core/linker/IFrameTemplate.js
@@ -120,7 +120,8 @@
     ,markerId = "__gwt_marker___MODULE_NAME__"
     ,markerScript;
 
-    if (base = metaProps['baseUrl']) {
+    if (metaProps['baseUrl']) {
+      base = metaProps['baseUrl'];
       return;
     }
 

dev/core/src/com/google/gwt/core/linker/XSTemplate.js

diff --git a/dev/core/src/com/google/gwt/core/linker/XSTemplate.js b/dev/core/src/com/google/gwt/core/linker/XSTemplate.js
index 204ec3f..b9b7c37 100644
--- a/dev/core/src/com/google/gwt/core/linker/XSTemplate.js
+++ b/dev/core/src/com/google/gwt/core/linker/XSTemplate.js
@@ -104,7 +104,8 @@
     ,markerId = "__gwt_marker___MODULE_NAME__"
     ,markerScript;
 
-    if (base = metaProps['baseUrl']) {
+    if (metaProps['baseUrl']) {
+      base = metaProps['baseUrl'];
       return;
     }