Pass path to platform kernel binary to kernel-service.

runtime/vm/isolate_reload_test.cc

Index: runtime/vm/isolate_reload_test.cc
diff --git a/runtime/vm/isolate_reload_test.cc b/runtime/vm/isolate_reload_test.cc
index cbe991bd7d588b05383db4fe4f0ec17f8c9d68a7..ef3682dfb7262e315c105df97791022c6e02c657 100644
--- a/runtime/vm/isolate_reload_test.cc
+++ b/runtime/vm/isolate_reload_test.cc
@@ -188,7 +188,7 @@ TEST_CASE(IsolateReload_KernelIncrementalCompileAppAndLib) {
   {
     void* kernel_pgm = NULL;
     char* error = TestCase::CompileTestScriptWithDFE(
-        "file:///test-app",
+        "file:///test-app.dart",
         sizeof(updated_sourcefiles) / sizeof(Dart_SourceFile),
         updated_sourcefiles, &kernel_pgm, true /* incrementally */);
     EXPECT(error == NULL);
@@ -263,7 +263,7 @@ TEST_CASE(IsolateReload_KernelIncrementalCompileGenerics) {
   {
     void* kernel_pgm = NULL;
     char* error = TestCase::CompileTestScriptWithDFE(
-        "file:///test-app",
+        "file:///test-app.dart",
         sizeof(updated_sourcefiles) / sizeof(Dart_SourceFile),
         updated_sourcefiles, &kernel_pgm, true /* incrementally */);
     EXPECT(error == NULL);