Introduce EditingStyleUtilities.{cpp,h}

third_party/WebKit/Source/core/editing/EditingStyleUtilities.h

+// Copyright 2017 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.
+
+#ifndef EditingStyleUtilities_h
+#define EditingStyleUtilities_h
+
+#include "core/CSSPropertyNames.h"
+#include "core/CSSValueKeywords.h"
+#include "core/editing/VisibleSelection.h"
+#include "core/editing/WritingDirection.h"
+
+namespace blink {
+
+class ContainerNode;
+class CSSStyleDeclaration;
+class EditingStyle;
+class MutableStylePropertySet;
+class Node;
+class StylePropertySet;
+
+class EditingStyleUtilities {
+  STATIC_ONLY(EditingStyleUtilities);
+
+ public:
+  static EditingStyle* createStyleAtSelectionStart(
+      const VisibleSelection&,
+      bool shouldUseBackgroundColorInEffect = false,
+      MutableStylePropertySet* styleToCheck = nullptr);
+  static EditingStyle* createWrappingStyleForSerialization(
+      ContainerNode* context);
+  static EditingStyle* createWrappingStyleForAnnotatedSerialization(
+      ContainerNode* context);
+  static WritingDirection textDirectionForSelection(
+      const VisibleSelection&,
+      EditingStyle* typingStyle,
+      bool& hasNestedOrMultipleEmbeddings);
+  static bool isEmbedOrIsolate(CSSValueID unicodeBidi) {
+    return unicodeBidi == CSSValueIsolate ||
+           unicodeBidi == CSSValueWebkitIsolate || unicodeBidi == CSSValueEmbed;
+  }
+
+  static bool isTransparentColorValue(const CSSValue*);
+  static bool hasTransparentBackgroundColor(CSSStyleDeclaration*);
+  static bool hasTransparentBackgroundColor(StylePropertySet*);
+  static const CSSValue* backgroundColorValueInEffect(Node*);
+  static bool hasAncestorVerticalAlignStyle(Node&, CSSValueID);
+};
+
+}  // namespace blink
+
+#endif  // EditingStyleUtilities_h