RFR(S) 8165603 - UseAppCDS.java failed to clean up files after test

[Ioi Lam]

https://bugs.openjdk.java.net/browse/JDK-8165603
http://cr.openjdk.java.net/~iklam/jdk11/8165603-files-not-closed.v01/

Summary:

The test case opens a temp file for reading without closing it 
explicitly. This causes
jtreg agentvm mode testing on Windows to complain about failing to 
delete the temp file.

The fix is to to put the opening of input/output streams in try-resource 
blocks, like

   try (BufferedReader br =
        new BufferedReader(
          new InputStreamReader(
           new FileInputStream(filename)))
   ) {
      for (; ; ) {
        String line = br.readLine();
      ...
   }

The streams will be closed when we leave the "try" block.

Besides the test in the bug report, I fixed a few other files in similar 
ways.

Testing -- HotSpot tier1/tier2 tests all passed. I verified that 
UseAppCDS.java
is now executed on Windows and passed.

I plan to push into the jdk/hs repo after the jdk 10 repo fork.

Thanks
- Ioi