gn format: Make parenthesizing better

tools/gn/format_test_data/057.gn

Index: tools/gn/format_test_data/057.gn
diff --git a/tools/gn/format_test_data/057.gn b/tools/gn/format_test_data/057.gn
new file mode 100644
index 0000000000000000000000000000000000000000..858e3115b11923bcc712b25a3ebe3e964b0e0e12
--- /dev/null
+++ b/tools/gn/format_test_data/057.gn
@@ -0,0 +1,24 @@
+# 80 ---------------------------------------------------------------------------
+# Because there is a difference in precedence level between || and &&
+#   a || b || c && d
+# is equivalent to
+#   a || b || (c && d)
+# Because parens are not stored in the parse tree, the formatter recreates the
+# minimally required set to maintain meaning. However, this particular case can
+# be confusing for human readers, so we special case these ones and add
+# strictly-unnecessary parens.
+
+supports_android = (is_apk || is_android_resources ||
+    (is_java_library && defined(invoker.supports_android) &&
+      invoker.supports_android))
+
+enable_one_click_signin = is_win || is_mac || (is_linux && !is_chromeos)
+enable_one_click_signin = (is_linux && !is_chromeos) || is_win || is_mac
+
+x = c || (a&&b)
+x = (a&&b) || c
+x = a&&b || c
+
+x = c && (a||b)
+x = (a||b) && c
+x = a||b && c