[dartfuzz] Make dart2js source available to the shards.

Change-Id: Ic2047f37f7de9b8d82f911b6a0c64a981619d0bb
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/365124
Reviewed-by: Siva Annamalai <asiva@google.com>
Reviewed-by: Alexander Aprelev <aam@google.com>
Commit-Queue: Ryan Macnak <rmacnak@google.com>

tools/bots/test_matrix.json

@@ -147,16 +147,7 @@
       "out/",
       "third_party/pkg/",
       "tools/sdks/dart-sdk/",
-      "pkg/_fe_analyzer_shared/",
-      "pkg/async_helper/",
-      "pkg/build_integration/",
-      "pkg/dart_internal/",
-      "pkg/expect/",
-      "pkg/front_end/",
-      "pkg/js/",
-      "pkg/kernel/",
-      "pkg/meta/",
-      "pkg/vm/",
+      "pkg/",
       "runtime/",
       "sdk/",
       ".dart_tool/package_config.json"