Hacky streaming of VariableGet

pkg/kernel/binary.md

Index: pkg/kernel/binary.md
diff --git a/pkg/kernel/binary.md b/pkg/kernel/binary.md
index bd89d60413832f382e1fb8b7d939cc2103a349da..098f697ab2703f072d6ab89bca0efb9ac92bd1fe 100644
--- a/pkg/kernel/binary.md
+++ b/pkg/kernel/binary.md
@@ -338,6 +338,7 @@ type InvalidExpression extends Expression {
 type VariableGet extends Expression {
   Byte tag = 20;
   FileOffset fileOffset;
+  UInt variableDeclarationPosition; // Notice that this field is temporary.

[Kevin Millikin (Google), 2017/04/05 08:59:57]

I don't think the comment belongs here.  But do say that it is the offset of the
declaration.

   VariableReference variable;
 }
 
@@ -345,6 +346,7 @@ type SpecializedVariableGet extends Expression {
   Byte tag = 128 + N; // Where 0 <= N < 8.
   // Equivalent to a VariableGet with index N.
   FileOffset fileOffset;
+  UInt variableDeclarationPosition; // Notice that this field is temporary.
 }
 
 type VariableSet extends Expression {