RFR: 8287102: ImageReaderSpi.canDecodeInput() for standard plugins should return false if a stream is too short [v2]

[Martin Desruisseaux]

> Invoking `ImageReaderSpi.canDecodeInput(Object)` with a stream having less than 8 bytes causes an `EOFException` to be thrown instead of returning `false`. This is caused by BMP, WBMP, GIF, PNG and TIFF reader implementations assuming that those bytes always exist and not checking EOF conditions. The JPEG reader is not impacted.
> 
> The `CanDecodeTest` class in this pull request reproduces the problem and verifies that the patch solves it. The changes in `canDecodeInput(Object)` method bodies are:
> 
> * Use `ImageInputStream.read()` instead of `readByte()` and check for -1 (EOF) return value.
> * Replace `ImageInputStream.readFully(byte[])` calls by a private `tryReadFully` method.

Martin Desruisseaux has updated the pull request incrementally with one additional commit since the last revision:

  Test all plugins, not only "BMP".

-------------

Changes:
  - all: https://git.openjdk.java.net/jdk/pull/8700/files
  - new: https://git.openjdk.java.net/jdk/pull/8700/files/a8737570..38f0cf34

Webrevs:
 - full: https://webrevs.openjdk.java.net/?repo=jdk&pr=8700&range=01
 - incr: https://webrevs.openjdk.java.net/?repo=jdk&pr=8700&range=00-01

  Stats: 1 line in 1 file changed: 0 ins; 0 del; 1 mod
  Patch: https://git.openjdk.java.net/jdk/pull/8700.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/8700/head:pull/8700

PR: https://git.openjdk.java.net/jdk/pull/8700