Add test harness option for app snapshots with unoptimized code.

runtime/include/dart_api.h

Index: runtime/include/dart_api.h
diff --git a/runtime/include/dart_api.h b/runtime/include/dart_api.h
index bc8c474ddc275e2963a38b7eec41b81752fc5149..d019d4fcea5bfe401be5ade8377c45bafb5fc291 100755
--- a/runtime/include/dart_api.h
+++ b/runtime/include/dart_api.h
@@ -2960,7 +2960,6 @@ DART_EXPORT Dart_Handle Dart_Precompile(
 
 /**
  *  Creates a precompiled snapshot.
- *   - The VM must not have been started from a snapshot.
  *   - A root library must have been loaded.
  *   - Dart_Precompile must have been called.
  *
@@ -2972,6 +2971,11 @@ DART_EXPORT Dart_Handle Dart_Precompile(
  *  The vm isolate snapshot, kInstructionsSnapshot and kDataSnapshot should be
  *  passed as arguments to Dart_Initialize. The isolate snapshot should be
  *  passed to Dart_CreateIsolate.
+ *
+ *  The buffers are scope allocated and are only valid until the next call to
+ *  Dart_ExitScope.
+ *
+ * \return A valid handle if no error occurs during the operation.
  */
 DART_EXPORT Dart_Handle Dart_CreatePrecompiledSnapshotAssembly(
     uint8_t** vm_isolate_snapshot_buffer,
@@ -3002,7 +3006,30 @@ DART_EXPORT Dart_Handle Dart_CreatePrecompiledSnapshotBlob(
 DART_EXPORT Dart_Handle Dart_PrecompileJIT();
 
 
-DART_EXPORT Dart_Handle Dart_CreatePrecompiledJITSnapshotBlob(
+/**
+ *  Creates a snapshot that caches unoptimized code and type feedback for faster
+ *  startup and quicker warmup in a subsequent process.
+ *
+ *  Outputs a snapshot in four pieces. The vm isolate snapshot,
+ *  instructions_blob and rodata_blob should be passed as arguments to
+ *  Dart_Initialize. The isolate snapshot should be passed to
+ *  Dart_CreateIsolate. The instructions piece must be loaded with execute
+ *  permissions; the other pieces may loaded as read-only.
+ *
+ *   - Requires the VM to have been started with --load-deferred-eagerly.
+ *   - Requires the VM to have not been started with --precompilation.
+ *   - Not supported when targeting IA32.
+ *   - The VM writing the snapshot and the VM reading the snapshot must be the
+ *     same version, must be built in the same DEBUG/RELEASE/PRODUCT mode, must
+ *     be targeting the same architecture, and must both be in checked mode or
+ *     both in unchecked mode.
+ *
+ *  The buffers are scope allocated and are only valid until the next call to
+ *  Dart_ExitScope.
+ *
+ * \return A valid handle if no error occurs during the operation.
+ */
+DART_EXPORT Dart_Handle Dart_CreateAppJITSnapshot(
     uint8_t** vm_isolate_snapshot_buffer,
     intptr_t* vm_isolate_snapshot_size,
     uint8_t** isolate_snapshot_buffer,