[GN] Generation failure caused by trailing space in file name

[myhsu]

Summary

Hi,

When I executed gn.py gen out/gn I got the following error:

ERROR at //compiler-rt/lib/builtins/BUILD.gn:162:7: Only source, header, and object files belong in the sources of a static_library. //compiler-rt/lib/builtins/emutls.c  is not one of the valid types.
      "emutls.c ",
      ^----------
See //compiler-rt/lib/BUILD.gn:3:5: which caused the file to be included.
    "//compiler-rt/lib/builtins",
    ^---------------------------

It turns out to be that the latest gn doesn't accept ill-format file name. And the emutls.c above has a trailing space.
Remove the trailing space should work.

[phosek]

LGTM

[myhsu]

Thanks for the review. I don't have commit permission, can you help me to commit?

llvm/trunk/utils/gn/secondary/compiler-rt/lib/builtins/BUILD.gn

sources = [
     # This depends on unwind.h which is present in Clang headers. We should
     # reconsider this if we ever decide to support building builtins with
     # other compilers.
     "gcc_personality_v0.c",
   ]
 
   if (target_os != "fuchsia") {
     sources += [
-      "emutls.c ",
+      "emutls.c",
       "enable_execute_stack.c",
       "eprintf.c",
     ]
   }
 
   if (target_os != "fuchsia" && !compiler_rt_baremetal_build) {
     sources += [
       # This comment prevents `gn format` from putting the file on the same line