Review: Removing GenerateNativeHeader where not needed

[Erik Joelsson]

The build infra project added the use of the annotation 
GenerateNativeHeader. It was addded to java classes without native 
methods that were listed in the old makefiles as needing headers 
generated for them. It was noted then that some of those classes didn't 
actually need native headers. To clean things up, we have tried to 
identify the empty headers and removed the annotation for those classes.

http://cr.openjdk.java.net/~erikj/build-infra-m1.2/webrev-jdk-awt/ 
<http://cr.openjdk.java.net/%7Eerikj/build-infra-m1.2/webrev-jdk-awt/>