Update GN toolchain_args to be a variable.

tools/gn/command_format.cc

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include <stddef.h>
 
 #include <sstream>
 
 #include "base/command_line.h"
 #include "base/files/file_util.h"
@@ skipping 489 matching lines @@
       parenthesized = true;
     } else {
       AddParen(prec_left, outer_prec, &parenthesized);
     }
 
     int start_line = CurrentLine();
     int start_column = CurrentColumn();
     bool is_assignment = binop->op().value() == "=" ||
                          binop->op().value() == "+=" ||
                          binop->op().value() == "-=";
-    // A sort of funny special case for the long lists that are common in .gn
-    // files, don't indent them + 4, even though they're just continuations when
-    // they're simple lists like "x = [ a, b, c, ... ]"
-    const ListNode* right_as_list = binop->right()->AsList();
-    int indent_column =
-        (is_assignment &&
-         (!right_as_list || (!right_as_list->prefer_multiline() &&
-                             !ListWillBeMultiline(right_as_list->contents(),
-                                                  right_as_list->End()))))
-            ? margin() + kIndentSize * 2
-            : start_column;
+
+    int indent_column = start_column;
+    if (is_assignment) {
+      // Default to a double-indent for wrapped assignments.
+      indent_column = margin() + kIndentSize * 2;
+
+      // A special case for the long lists and scope assignments that are
+      // common in .gn files, don't indent them + 4, even though they're just
+      // continuations when they're simple lists like "x = [ a, b, c, ... ]" or
+      // scopes like "x = { a = 1 b = 2 }". Put back to "normal" indenting.
+      const ListNode* right_as_list = binop->right()->AsList();
+      if (right_as_list) {
+        if (right_as_list->prefer_multiline() ||
+            ListWillBeMultiline(right_as_list->contents(),
+                                right_as_list->End()))
+          indent_column = start_column;
+      } else {
+        const BlockNode* right_as_block = binop->right()->AsBlock();
+        if (right_as_block)
+          indent_column = start_column;
+      }
+    }
     if (stack_.back().continuation_requires_indent)
       indent_column += kIndentSize * 2;
 
     stack_.push_back(IndentState(indent_column,
                                  stack_.back().continuation_requires_indent,
                                  binop->op().value() == "||"));
     Printer sub_left;
     InitializeSub(&sub_left);
     sub_left.Expr(binop->left(),
                   prec_left,
@@ skipping 540 matching lines @@
       }
     } else {
       printf("%s", output_string.c_str());
     }
   }
 
   return 0;
 }
 
 }  // namespace commands