Avoid system fonts when fuzzing

This should make reproducing certain fuzzes easier between oss-fuzz
and a typical dev's desktop.

This was the most straight-forward way I could think of to
accomplish this.  An ideal solution would "compile" a set of
fonts that was not the test set and embed it, but I lack the
domain knowledge to craft such a set.

If this method works ok, we can explore making the font set
more robust and varied.

Bug: 818769
Change-Id: I03eb2bc316caf7aec3ffa88e59ff29d76c8557ec
Reviewed-on: https://skia-review.googlesource.com/c/177800
Commit-Queue: Kevin Lubick <kjlubick@google.com>
Reviewed-by: Ben Wagner <bungeman@google.com>
diff --git a/BUILD.gn b/BUILD.gn
index 4353580..a6fcb0b 100644
--- a/BUILD.gn
+++ b/BUILD.gn
@@ -656,7 +656,8 @@
       public_defines += [ "SK_ENABLE_VK_LAYERS" ]
     }
     if (is_fuchsia) {
-      public_deps += [ "//third_party/vulkan_loader_and_validation_layers:vulkan" ]
+      public_deps +=
+          [ "//third_party/vulkan_loader_and_validation_layers:vulkan" ]
     }
   }
 
@@ -1909,6 +1910,7 @@
     include_dirs = [
       "tools",
       "tools/debugger",
+      "tools/fonts",
     ]
     sources = [
       "fuzz/Fuzz.cpp",