Fix unintended spec change: Final fields not being initialized is only a warning.

docs/language/dartLangSpec.tex

Index: docs/language/dartLangSpec.tex
diff --git a/docs/language/dartLangSpec.tex b/docs/language/dartLangSpec.tex
index a01d8eb2d9c4a9a652bc909f2ef32efd54afa749..8232a3b4554b93cacaa92e9b401d0c7e8bc3ae9d 100644
--- a/docs/language/dartLangSpec.tex
+++ b/docs/language/dartLangSpec.tex
@@ -1390,8 +1390,7 @@ in the order they appear in the program.
 \LMHash{}
 Then if any instance variable of $i$ declared by the immediately enclosing class
 is not yet bound to a value,
-it is a dynamic error if such a variable is a \FINAL{} variable,
-otherwise all such variables are initialized with the \NULL{} value.
+all such variables are initialized with the \NULL{} value.

[eernst, 2016/12/02 14:09:46]

Yeah, we shouldn't have finished https://codereview.chromium.org/2399343002 so
quickly. ;-)

 
 \LMHash{}
 Then, unless the enclosing class is \code{Object}, the explicitly specified or