- Refactor the way X.fromEnvironment is implemented.

runtime/vm/symbols.h

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #ifndef VM_SYMBOLS_H_
 #define VM_SYMBOLS_H_
 
 #include "vm/object.h"
 #include "vm/snapshot_ids.h"
 
@@ skipping 113 matching lines @@
   V(LanguageError, "LanguageError")                                            \
   V(UnhandledException, "UnhandledException")                                  \
   V(UnwindError, "UnwindError")                                                \
   V(IntegerImplementation, "_IntegerImplementation")                           \
   V(Number, "num")                                                             \
   V(_Smi, "_Smi")                                                              \
   V(_Mint, "_Mint")                                                            \
   V(_Bigint, "_Bigint")                                                        \
   V(_Double, "_Double")                                                        \
   V(Bool, "bool")                                                              \
+  V(True, "true")                                                              \
+  V(False, "false")                                                            \
   V(_List, "_List")                                                            \
   V(_ListFactory, "_List.")                                                    \
   V(_GrowableList, "_GrowableList")                                            \
   V(_GrowableListFactory, "_GrowableList.")                                    \
   V(_GrowableListWithData, "_GrowableList.withData")                           \
   V(_ImmutableList, "_ImmutableList")                                          \
   V(_LinkedHashMap, "_InternalLinkedHashMap")                                  \
   V(_String, "String")                                                         \
   V(OneByteString, "_OneByteString")                                           \
   V(TwoByteString, "_TwoByteString")                                           \
@@ skipping 163 matching lines @@
   V(hashCode, "get:hashCode")                                                  \
   V(_leftShiftWithMask32, "_leftShiftWithMask32")                              \
   V(OptimizedOut, "<optimized out>")                                           \
   V(NotInitialized, "<not initialized>")                                       \
   V(AllocationStubFor, "Allocation stub for ")                                 \
   V(TempParam, ":temp_param")                                                  \
   V(_UserTag, "_UserTag")                                                      \
   V(Default, "Default")                                                        \
   V(StubPrefix, "[Stub] ")                                                     \
   V(ClassID, "ClassID")                                                        \
+  V(DartIsVM, "dart.isVM")                                                     \
 
 
 // Contains a list of frequently used strings in a canonicalized form. This
 // list is kept in the vm_isolate in order to share the copy across isolates
 // without having to maintain copies in each isolate.
 class Symbols : public AllStatic {
  public:
   enum { kMaxOneCharCodeSymbol = 0xFF };
 
   // List of strings that are pre created in the vm isolate.
@@ skipping 176 matching lines @@
   friend class SnapshotReader;
   friend class SnapshotWriter;
   friend class ApiMessageReader;
 
   DISALLOW_COPY_AND_ASSIGN(Symbols);
 };
 
 }  // namespace dart
 
 #endif  // VM_SYMBOLS_H_