[LPM] Disable debug builds for skia_image_filter_proto_fuzzer on CF.

TBR=mbarbella@chromium.org

Bug: 769578
Change-Id: Id2039ce1c97d42723c5616c4655d2c9c39ed130f
Reviewed-on: https://chromium-review.googlesource.com/897984Reviewed-by: Jonathan Metzman <metzman@chromium.org>
Reviewed-by: Martin Barbella <mbarbella@chromium.org>
Commit-Queue: Jonathan Metzman <metzman@chromium.org>
Cr-Commit-Position: refs/heads/master@{#533757}

testing/libfuzzer/proto/BUILD.gn

@@ -57,6 +57,9 @@ if (!is_win) {
 
     # Assertion failures in skia are uninteresting. Don't use debug builds on
     # CF.
+    if (is_debug) {
+      all_dependent_configs = [ "//testing/libfuzzer:no_clusterfuzz" ]
+    }
   }
 
   proto_library("skia_image_filter_proto") {