Add common test configs for properties that take lengths

third_party/WebKit/LayoutTests/typedcssom/inlinestyle/properties/left.html

Index: third_party/WebKit/LayoutTests/typedcssom/inlinestyle/properties/left.html
diff --git a/third_party/WebKit/LayoutTests/typedcssom/inlinestyle/properties/border-bottom-style.html b/third_party/WebKit/LayoutTests/typedcssom/inlinestyle/properties/left.html
similarity index 58%
copy from third_party/WebKit/LayoutTests/typedcssom/inlinestyle/properties/border-bottom-style.html
copy to third_party/WebKit/LayoutTests/typedcssom/inlinestyle/properties/left.html
index 6564e7fd3224eb366f2c6e17c1b6cb771fff31ac..31d1ff6c039a146f2019aebed46aad418932e835 100644
--- a/third_party/WebKit/LayoutTests/typedcssom/inlinestyle/properties/border-bottom-style.html
+++ b/third_party/WebKit/LayoutTests/typedcssom/inlinestyle/properties/left.html
@@ -3,9 +3,9 @@
 <script src='../../../resources/testharnessreport.js'></script>
 <script src='property-suite.js'></script>
 <script src='config-templates.js'></script>
-
 <script>
-  let config = Object.assign({}, config_templates.borderConfig);
-  config['property'] = 'border-bottom-style';
-  runInlineStylePropertyMapTests(config);
-</script>
+let config = config_templates.lengthPercentConfig();
+config['property'] = 'left';
+config['validKeywords'] = ['auto'];
+runInlineStylePropertyMapTests(config);
+</script>