Windows, java/python/sh launcher: don't use cmd.exe's "copy" to concat binaries

Bazel uses cmd.exe’s copy command to concat the launcher stub and the java/python/sh binary. This is how we get .exe files as {java/py/sh}_binary outputs.

The rules create an action that concats the launcher (a C++ binary) and the launch info (properties of the actual binary such as main class name + the binary itself):

bin/bash.exe -c cmd.exe /c "copy /Y /B external\bazel_tools\tools\launcher\launcher.exe+bazel-out\host\bin\external\bazel_tools\src\tools\android\java\com\google\devtools\build\android\ResourceProcessorBusyBox.launch_info bazel-out\host\bin\external\bazel_tools\src\tools\android\java\com\google\devtools\build\android\ResourceProcessorBusyBox.exe > nul".

However cmd.exe cannot handle long paths, therefore this action also doesn’t.

[laszlocsomor]

Yes. I’m reviving Yun’s LauncherFileWriteAction.

[laszlocsomor]

Yes, that sounds like a good idea. It pivots around https://github.com/bazelbuild/bazel/issues/2870 though, but I’m working on it as we speak.