Fix off-by-one error in enforcement of WebGL's maximum struct nesting.

BUG=http://code.google.com/p/angleproject/issues/detail?id=275
TEST=WebGL conformance suite
TBR=nicolas
Review URL: http://codereview.appspot.com/5520049

git-svn-id: https://angleproject.googlecode.com/svn/trunk@938 736b8ea6-26fd-11df-bfd4-992fa37f6226
diff --git a/src/compiler/ParseHelper.cpp b/src/compiler/ParseHelper.cpp
index 529fbef..431f8d1 100644
--- a/src/compiler/ParseHelper.cpp
+++ b/src/compiler/ParseHelper.cpp
@@ -1463,7 +1463,7 @@
 
     // We're already inside a structure definition at this point, so add
     // one to the field's struct nesting.
-    if (1 + fieldType.getDeepestStructNesting() >= kWebGLMaxStructNesting) {
+    if (1 + fieldType.getDeepestStructNesting() > kWebGLMaxStructNesting) {
         error(line, "", "", "Reference of struct type %s exceeds maximum struct nesting of %d",
               fieldType.getTypeName().c_str(), kWebGLMaxStructNesting);
         return true;