Special-case paths that appear in libs by not prefixing them with -l.

tools/gn/variables.cc

Index: tools/gn/variables.cc
diff --git a/tools/gn/variables.cc b/tools/gn/variables.cc
index d79c3aa887defcdf0101ab393ca6099bd7c71b3b..1e886dd71cd18a96d6c0b0e6ae502ba9ae2e085e 100644
--- a/tools/gn/variables.cc
+++ b/tools/gn/variables.cc
@@ -892,9 +892,12 @@ const char kLibs_HelpShort[] =
 const char kLibs_Help[] =
     "libs: Additional libraries to link.\n"
     "\n"
-    "  A list of strings.\n"
+    "  A list of library names or library paths.\n"
+    "\n"
+    "  Values containing '/' will be treated as paths, and those without will\n"
+    "  be treated as library names."
     "\n"
-    "  These files will be passed to the linker, which will generally search\n"
+    "  Names will be passed to the linker, which will generally search\n"
     "  the library include path. Unlike a normal list of files, they will be\n"
     "  passed to the linker unmodified rather than being treated as file\n"
     "  names relative to the current build file. Generally you would set\n"
@@ -904,8 +907,8 @@ const char kLibs_Help[] =
     "\n"
     "  When constructing the linker command, the \"lib_prefix\" attribute of\n"
     "  the linker tool in the current toolchain will be prepended to each\n"
-    "  library. So your BUILD file should not specify the switch prefix\n"
-    "  (like \"-l\").\n"
+    "  library name (but not library paths). Your BUILD file should not\n"
+    "  specify the switch prefix (like \"-l\").\n"
     "\n"
     "  Libraries ending in \".framework\" will be special-cased: the switch\n"
     "  \"-framework\" will be prepended instead of the lib_prefix, and the\n"