[skottie] Fix spurious gradient error messages

The adapter apply() method can get called before stops resolution, so
only log when some stops are present.

TBR=

Change-Id: I8e336e2cff781a0e64de31e6b63f3cf373b2daa0
Reviewed-on: https://skia-review.googlesource.com/140245
Reviewed-by: Florin Malita <fmalita@chromium.org>
Commit-Queue: Florin Malita <fmalita@chromium.org>
diff --git a/modules/skottie/src/SkottieAdapter.cpp b/modules/skottie/src/SkottieAdapter.cpp
index 615390e..f4bb0a8 100644
--- a/modules/skottie/src/SkottieAdapter.cpp
+++ b/modules/skottie/src/SkottieAdapter.cpp
@@ -94,7 +94,10 @@
     // |fColorStops| holds |fStopCount| x [ pos, r, g, g ] + ? x [ pos, alpha ]
 
     if (fColorStops.size() < fStopCount * 4 || ((fColorStops.size() - fStopCount * 4) % 2)) {
-        SkDebugf("!! Invalid gradient stop array size: %zu", fColorStops.size());
+        // apply() may get called before the stops are set, so only log when we have some stops.
+        if (!fColorStops.empty()) {
+            SkDebugf("!! Invalid gradient stop array size: %zu\n", fColorStops.size());
+        }
         return;
     }