[ignition] Add bytecodes for loads/stores in the current context

test/cctest/interpreter/bytecode_expectations/CountOperators.golden

 #
 # Autogenerated by generate-bytecode-expectations.
 #
 
 ---
 wrap: yes
 
 ---
 snippet: "
   var a = 1; return ++a;
@@ skipping 179 matching lines @@
 ]
 handlers: [
 ]
 
 ---
 snippet: "
   var a = 1; var b = function() { return a }; return ++a;
 "
 frame size: 2
 parameter count: 1
-bytecode array length: 27
+bytecode array length: 21
 bytecodes: [
                 B(CreateFunctionContext), U8(1),
                 B(PushContext), R(1),
   /*   30 E> */ B(StackCheck),
   /*   42 S> */ B(LdaSmi), U8(1),
-  /*   42 E> */ B(StaContextSlot), R(context), U8(4), U8(0),
+  /*   42 E> */ B(StaCurrentContextSlot), U8(4),
   /*   53 S> */ B(CreateClosure), U8(0), U8(2),
                 B(Star), R(0),
-  /*   78 S> */ B(LdaContextSlot), R(context), U8(4), U8(0),
+  /*   78 S> */ B(LdaCurrentContextSlot), U8(4),
                 B(Inc), U8(2),
-  /*   87 E> */ B(StaContextSlot), R(context), U8(4), U8(0),
+  /*   87 E> */ B(StaCurrentContextSlot), U8(4),
   /*   90 S> */ B(Return),
 ]
 constant pool: [
   SHARED_FUNCTION_INFO_TYPE,
 ]
 handlers: [
 ]
 
 ---
 snippet: "
   var a = 1; var b = function() { return a }; return a--;
 "
 frame size: 3
 parameter count: 1
-bytecode array length: 31
+bytecode array length: 25
 bytecodes: [
                 B(CreateFunctionContext), U8(1),
                 B(PushContext), R(1),
   /*   30 E> */ B(StackCheck),
   /*   42 S> */ B(LdaSmi), U8(1),
-  /*   42 E> */ B(StaContextSlot), R(context), U8(4), U8(0),
+  /*   42 E> */ B(StaCurrentContextSlot), U8(4),
   /*   53 S> */ B(CreateClosure), U8(0), U8(2),
                 B(Star), R(0),
-  /*   78 S> */ B(LdaContextSlot), R(context), U8(4), U8(0),
+  /*   78 S> */ B(LdaCurrentContextSlot), U8(4),
                 B(ToNumber), R(2),
                 B(Dec), U8(2),
-  /*   86 E> */ B(StaContextSlot), R(context), U8(4), U8(0),
+  /*   86 E> */ B(StaCurrentContextSlot), U8(4),
                 B(Ldar), R(2),
   /*   90 S> */ B(Return),
 ]
 constant pool: [
   SHARED_FUNCTION_INFO_TYPE,
 ]
 handlers: [
 ]
 
 ---
@@ skipping 16 matching lines @@
                 B(LdaSmi), U8(2),
   /*   79 E> */ B(StaKeyedPropertySloppy), R(1), R(3), U8(3),
   /*   84 S> */ B(Return),
 ]
 constant pool: [
   FIXED_ARRAY_TYPE,
 ]
 handlers: [
 ]