runtime: Make kIsDebugBuild friendly to clion

Previously it would think

   if (kIsDebugBuild)

was always dead code and give many warnings.

Also make sure that clion inspector doesn't try to be too clever
and suggest that kIsDebugBuild is always true, which was
equally annoying.

Bug: b/64455231
Change-Id: I8db6b7cec2024f4cc7ad3353f2ee695c4fec1d8f