RFR: JDK-8250217: com.sun.tools.javac.api.JavacTaskImpl swallows compiler exceptions potentially producing false positive test results

[Vicente Romero]

Hi,

Please review fix for [1] at [2]. While fixing a bug a while ago I 
realized that com.sun.tools.javac.api.JavacTaskImpl could swallow 
compiler exceptions implying that for the invoking test, the compilation 
went fine and so the test was incorrectly passing. With this patch, 
JavacTaskImpl is now grumpier so that clients can't make the false 
assumption that the compilation passed. The patch is also fixing a test 
that was passing for the wrong reason,

Thanks,
Vicente

[1] https://bugs.openjdk.java.net/browse/JDK-8250217
[2] http://cr.openjdk.java.net/~vromero/8250217/webrev.00/