First step towards splitting a full snapshot into a vm isolate snapshot and a

runtime/include/dart_api.h

Index: runtime/include/dart_api.h
===================================================================
--- runtime/include/dart_api.h	(revision 44745)
+++ runtime/include/dart_api.h	(working copy)
@@ -825,6 +825,8 @@
 /**
  * Initializes the VM.
  *
+ * \param vm_isolate_snapshot A buffer containing a snapshot of the VM isolate
+ *   or NULL if no snapshot is provided.
  * \param create A function to be called during isolate creation.
  *   See Dart_IsolateCreateCallback.
  * \param interrupt A function to be called when an isolate is interrupted.
@@ -837,6 +839,7 @@
  * \return True if initialization is successful.
  */
 DART_EXPORT bool Dart_Initialize(
+    const uint8_t* vm_isolate_snapshot,
     Dart_IsolateCreateCallback create,
     Dart_IsolateInterruptCallback interrupt,
     Dart_IsolateUnhandledExceptionCallback unhandled_exception,
@@ -889,8 +892,8 @@
  *   Provided only for advisory purposes to improve debugging messages.
  * \param main The name of the main entry point this isolate will run.
  *   Provided only for advisory purposes to improve debugging messages.
- * \param snapshot A buffer containing a VM snapshot or NULL if no
- *   snapshot is provided.
+ * \param snapshot A buffer containing a snapshot of the isolate or
+ *   NULL if no snapshot is provided.
  * \param callback_data Embedder data.  This data will be passed to
  *   the Dart_IsolateCreateCallback when new isolates are spawned from
  *   this parent isolate.
@@ -992,9 +995,10 @@
 /**
  * Creates a full snapshot of the current isolate heap.
  *
- * A full snapshot is a compact representation of the dart heap state and
- * can be used for fast initialization of an isolate. A Snapshot of the heap
- * can only be created before any dart code has executed.
+ * A full snapshot is a compact representation of the dart vm isolate heap
+ * and dart isolate heap states. These snapshots are used to initialize
+ * the vm isolate on startup and fast initialization of an isolate.
+ * A Snapshot of the heap is created before any dart code has executed.
  *
  * Requires there to be a current isolate.
  *
@@ -1005,8 +1009,11 @@
  *
  * \return A valid handle if no error occurs during the operation.
  */
-DART_EXPORT Dart_Handle Dart_CreateSnapshot(uint8_t** buffer,
-                                            intptr_t* size);
+DART_EXPORT Dart_Handle Dart_CreateSnapshot(
+    uint8_t** vm_isolate_snapshot_buffer,
+    intptr_t* vm_isolate_snapshot_size,
+    uint8_t** isolate_snapshot_buffer,
+    intptr_t* isolate_snapshot_size);
 
 /**
  * Creates a snapshot of the application script loaded in the isolate.