Coarsen deep hash code calculation for ObjectCodecRegistry: lambdas' …

…suffixes are non-deterministic. The integer index before the '/' character should be deterministic, but doesn't seem to be.

PiperOrigin-RevId: 218918204

src/main/java/com/google/devtools/build/lib/skyframe/serialization/ObjectCodecRegistry.java

@@ -447,6 +447,13 @@ private int deepHashCode() {
   }
 
   private static int hashClass(Class<?> clazz) {
+    if (LambdaCodec.isProbablyLambda(clazz)) {
+      String name = clazz.getName();
+      int indexOfLambda = name.lastIndexOf("$$Lambda$");
+      if (indexOfLambda > -1) {
+        return name.substring(0, indexOfLambda + 9).hashCode();
+      }
+    }
     return clazz.getName().hashCode();
   }
 }