Change function source fingerprint calculation to rely on tokens exclusively and

runtime/vm/object_test.cc

Index: runtime/vm/object_test.cc
diff --git a/runtime/vm/object_test.cc b/runtime/vm/object_test.cc
index 6622d8bd7bca4d3e6872b799cef2585628a933b5..e793b9bb1d870e785bfc0dc36511f9b20f9af400 100644
--- a/runtime/vm/object_test.cc
+++ b/runtime/vm/object_test.cc
@@ -4034,7 +4034,11 @@ TEST_CASE(FunctionSourceFingerprint) {
   EXPECT_NE(a_test3.SourceFingerprint(), a_test4.SourceFingerprint());
   EXPECT_NE(a_test4.SourceFingerprint(), a_test5.SourceFingerprint());
   EXPECT_EQ(a_test5.SourceFingerprint(), b_test5.SourceFingerprint());
-  EXPECT_NE(a_test6.SourceFingerprint(), b_test6.SourceFingerprint());
+  // Although a_test6's receiver type is different than b_test6's receiver type,
+  // the fingerprints are identical. The token stream does not reflect the
+  // receiver's type. This is not a problem, since we recognize functions
+  // of a given class and of a given name.
+  EXPECT_EQ(a_test6.SourceFingerprint(), b_test6.SourceFingerprint());
 }