please review 7122061: enable -Werror in various jdk build steps

[Stuart Marks]

The webrev is here:

http://cr.openjdk.java.net/~smarks/reviews/7122061/webrev.0/

This defines the JAVAC_MAX_WARNINGS and JAVAC_WARNINGS_FATAL variables in a 
variety of Makefiles within the jdk repository. This essentially adds 
-Xlint:all -Werror to the javac command lines, so that henceforth if any lint 
warnings are introduced, the build will fail.

I'm applying these flags only to build steps that are already warnings free. 
(Last week's warnings cleanup effort cleared warnings from four build steps, in 
addition to knocking off a couple thousand warnings across the build.) I've 
applied this change and have built successfully on all platforms.

With this change, 57 of the 93 javac build steps in the jdk repo are now lint 
warning free, and are protected from the introduction of new errors through the 
use of -Werror.

Thanks,

s'marks