Move dart2js from sdk/lib/_internal/compiler to pkg/compiler

sdk/bin/dart2js_sdk

Index: sdk/bin/dart2js_sdk
diff --git a/sdk/bin/dart2js b/sdk/bin/dart2js_sdk
similarity index 86%
copy from sdk/bin/dart2js
copy to sdk/bin/dart2js_sdk
index 79a857be83efe500109c4f7c760fa2a9c008f2f9..5d7ec9c689023ad223726139e3ac5f3320cc0266 100755
--- a/sdk/bin/dart2js
+++ b/sdk/bin/dart2js_sdk
@@ -20,8 +20,6 @@ BIN_DIR="$(cd "${PROG_NAME%/*}" ; pwd -P)"
 
 SDK_DIR="$(cd "${BIN_DIR}/.." ; pwd -P)"
 
-DART2JS="$SDK_DIR/lib/_internal/compiler/implementation/dart2js.dart"
-
 DART="$BIN_DIR/dart"
 
 SNAPSHOT_DIR="$BIN_DIR/snapshots"
@@ -63,8 +61,4 @@ if [[ $DART_VM_OPTIONS ]]; then
   EXTRA_VM_OPTIONS+=("${OPTIONS[@]}")
 fi
 
-if test -f "$SNAPSHOT"; then
-  exec "$DART" "${EXTRA_VM_OPTIONS[@]}" "$SNAPSHOT" "${EXTRA_OPTIONS[@]}" "$@"
-else
-  exec "$DART" "${EXTRA_VM_OPTIONS[@]}" "$DART2JS" "${EXTRA_OPTIONS[@]}" "$@"
-fi
+exec "$DART" "${EXTRA_VM_OPTIONS[@]}" "$SNAPSHOT" "${EXTRA_OPTIONS[@]}" "$@"