Merge topic 'ninja-absolute-paths'

c564a3e3ff Ninja: Always compile sources using absolute paths
eb98d45111 Ninja: Handle depfiles with absolute paths to generated files in Ninja < 1.7
48471cfd18 cmNinjaNormalTargetGenerator: Factor out build event byproduct collection
18408c0b88 cmGlobalNinjaGenerator: Add helper to compute absolute paths for build.ninja
efb8d7b4a1 cmNinjaTargetGenerator: Reduce string copies in ConvertToNinjaPath wrapper
fb3a57575a cmNinjaTargetGenerator: Rename source file path lookup method for clarity
0f2b1c9d1b cmNinjaTargetGenerator: Remove GetSourceFilePath call with different semantics
dfc98774a2 cmNinjaTargetGenerator: Rename local variable for clarity
...

Acked-by: Kitware Robot <kwrobot@kitware.com>
Acked-by: Ben Boeckel <ben.boeckel@kitware.com>
Merge-request: !6148