[7u8] Request for approval: 7181438 [OGL] Incorrect alpha used, during blit from SW to the texture.

[Sergey Bylokhov]

Hi Everyone,
This is a direct back port from jdk 8 to jdk 7u8.

Bug: http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=7181438
Webrev can be found at: http://cr.openjdk.java.net/~serb/7181438/webrev.01
Discussion for jdk8 review: 
http://mail.openjdk.java.net/pipermail/2d-dev/2012-July/002630.html
jdk8 changeset: http://hg.openjdk.java.net/jdk8/awt/jdk/rev/4624486823a7

Reviewers: Andrew Brygin

-- 
Best regards, Sergey.