[package:dartdev] Make dartdev's Sdk class correctly return paths to PRODUCT snapshots when necessary

This makes the class return paths to PRODUCT snapshots if and only if it is under the conditions that would make it return the path to a PRODUCT dartaotruntime.

TEST=manual testing, CI

Change-Id: I2544c7bc58625d85d34ff3506c10821484e75f1e
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/396500
Reviewed-by: Ben Konyi <bkonyi@google.com>
Commit-Queue: Derek Xu <derekx@google.com>

pkg/dartdev/lib/src/sdk.dart

@@ -71,17 +71,25 @@ class Sdk {
         'dartdevc.dart.snapshot',
       );
 
-  String get ddcAotSnapshot => _snapshotPathFor(
-        'dartdevc_aot.dart.snapshot',
-      );
+  String get ddcAotSnapshot => _runFromBuildRoot
+      ? _snapshotPathFor(
+          'dartdevc_aot_product.dart.snapshot',
+        )
+      : _snapshotPathFor(
+          'dartdevc_aot.dart.snapshot',
+        );
 
   String get dart2jsSnapshot => _snapshotPathFor(
         'dart2js.dart.snapshot',
       );
 
-  String get dart2jsAotSnapshot => _snapshotPathFor(
-        'dart2js_aot.dart.snapshot',
-      );
+  String get dart2jsAotSnapshot => _runFromBuildRoot
+      ? _snapshotPathFor(
+          'dart2js_aot_product.dart.snapshot',
+        )
+      : _snapshotPathFor(
+          'dart2js_aot.dart.snapshot',
+        );
 
   String get dart2wasmSnapshot => _snapshotPathFor(
         'dart2wasm_product.snapshot',
@@ -99,9 +107,13 @@ class Sdk {
         'frontend_server.dart.snapshot',
       );
 
-  String get frontendServerAotSnapshot => _snapshotPathFor(
-        'frontend_server_aot.dart.snapshot',
-      );
+  String get frontendServerAotSnapshot => _runFromBuildRoot
+      ? _snapshotPathFor(
+          'frontend_server_aot_product.dart.snapshot',
+        )
+      : _snapshotPathFor(
+          'frontend_server_aot.dart.snapshot',
+        );
 
   String get dtdSnapshot => _snapshotPathFor(
         'dart_tooling_daemon.dart.snapshot',