Make the Skia GN build work.

On Linux, at least.

BUG=pdfium:11

Review-Url: https://codereview.chromium.org/1971023007
diff --git a/skia/skia_library.gypi b/skia/skia_library.gypi
index dd3d240..a4eb0ab 100644
--- a/skia/skia_library.gypi
+++ b/skia/skia_library.gypi
@@ -5,7 +5,7 @@
 
 # This gypi file contains the Skia library.
 # In component mode (shared_lib) it is folded into a single shared library with
-# the Chrome-specific enhancements but in all other cases it is a separate lib.
+# the PDFium-specific enhancements but in all other cases it is a separate lib.
 
 # !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!WARNING!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
 # variables and defines should go in skia_common.gypi so they can be seen