[Driver] Escape the program path for -frecord-command-line

Similar to the rest of the command line that is recorded, the program
path must also have spaces and backslashes escaped. Without this
parsing the recorded command line becomes hard on platforms like
Windows where spaces and backslashes are common.

This was originally reverted in
577d9ce3; this version makes a test
agnostic to the presence of backslashes in paths on some platforms.

Patch By: Ravi Ramaseshan
Differential Revision: https://reviews.llvm.org/D74811