Description of problem:

This is the same issue as https://issues.apache.org/bugzilla/show_bug.cgi?id=55842

When using the response writer, we end up just flushing the buffer in org.apache.catalina.connector.OutputBuffer.realWriteChars instead of trying to grow the buffer.


Version-Release number of selected component (if applicable):

Web 7.5.7


How reproducible:

Always

Steps to Reproduce:
1. response.setBufferSize(#) to increase buffer size
2. response.getWriter() and write data greater than the initial buffer size but less than the increased buffer size
3. check response.isCommitted() to see that the data has already been flushed and the response committed instead of the buffer's being expanded


Actual results:

Buffer is flushed upon reaching the initial buffer size instead of growing up to the buffer limit increased by response.setBufferSize(#)


Expected results:

Buffer grows up to the increased limit when using the response writer


Additional info:

Fix for 7.5.x: r2603