Extend the use of response files to cover the case when emcc invokes emscripten.py, so that Windows command line length limitations don't break the test_asm_pgo on Windows.
Fix typo.
Don't require response files to end with '.rsp'. Only autodelete response files that end with the suffix '.tmp'. Use the suffix '.tmp' for all internally utilized response files.
Remove the unwanted abstraction that callee is allowed to autodelete a response file after consuming it. Instead, manually track and delete response files by the caller and clean them up.
Remove duplicate line from rebase.
Merge pull request #1038 from juj/fix_test_asm_pgo_windows

Fix test_asm_pgo on Windows.