Update android_make to support both --gcc and --clang options.

This CL also fixes all the errors that resulted from compiling
with clang and ccache.

BUG=skia:4948
GOLD_TRYBOT_URL= https://gold.skia.org/search2?unt=true&query=source_type%3Dgm&master=false&issue=1774503004

Review URL: https://codereview.chromium.org/1774503004
diff --git a/gyp/freetype.gyp b/gyp/freetype.gyp
index 94ab94c..f282f77 100644
--- a/gyp/freetype.gyp
+++ b/gyp/freetype.gyp
@@ -102,6 +102,11 @@
             '-O2',
           ],
         }],
+        [ 'skia_clang_build == 1', {
+          'cflags':[
+            '-Wno-error',
+          ],
+        }],
       ],
     },
   ],