CSS4: Implement :placeholder-shown pseudo class

Source/core/html/HTMLTextAreaElement.cpp

Index: Source/core/html/HTMLTextAreaElement.cpp
diff --git a/Source/core/html/HTMLTextAreaElement.cpp b/Source/core/html/HTMLTextAreaElement.cpp
index ae4aa22442000f1de019f3b142435cefb8b923b7..3441312a86a368e49c1f3a26ea6d717ed23359ba 100644
--- a/Source/core/html/HTMLTextAreaElement.cpp
+++ b/Source/core/html/HTMLTextAreaElement.cpp
@@ -274,7 +274,7 @@ void HTMLTextAreaElement::subtreeHasChanged()
     m_valueIsUpToDate = false;
     setNeedsValidityCheck();
     setAutofilled(false);
-    updatePlaceholderVisibility(false);
+    updatePlaceholderVisibility();
 
     if (!focused())
         return;
@@ -332,7 +332,7 @@ void HTMLTextAreaElement::updateValue() const
     const_cast<HTMLTextAreaElement*>(this)->m_valueIsUpToDate = true;
     const_cast<HTMLTextAreaElement*>(this)->notifyFormStateChanged();
     m_isDirty = true;
-    const_cast<HTMLTextAreaElement*>(this)->updatePlaceholderVisibility(false);
+    const_cast<HTMLTextAreaElement*>(this)->updatePlaceholderVisibility();
 }
 
 String HTMLTextAreaElement::value() const
@@ -384,7 +384,7 @@ void HTMLTextAreaElement::setValueCommon(const String& newValue, TextFieldEventB
     setInnerEditorValue(m_value);
     if (eventBehavior == DispatchNoEvent)
         setLastChangeWasNotUserEdit();
-    updatePlaceholderVisibility(false);
+    updatePlaceholderVisibility();
     setNeedsStyleRecalc(SubtreeStyleChange, StyleChangeReasonForTracing::create(StyleChangeReason::ControlValue));
     m_suggestedValue = String();
     setNeedsValidityCheck();
@@ -499,7 +499,7 @@ void HTMLTextAreaElement::setSuggestedValue(const String& value)
         setInnerEditorValue(m_suggestedValue);
     else
         setInnerEditorValue(m_value);
-    updatePlaceholderVisibility(false);
+    updatePlaceholderVisibility();
     setNeedsStyleRecalc(SubtreeStyleChange, StyleChangeReasonForTracing::create(StyleChangeReason::ControlValue));
 }
 
@@ -618,6 +618,7 @@ void HTMLTextAreaElement::updatePlaceholderText()
         placeholder = newElement.get();
         placeholder->setShadowPseudoId(AtomicString("-webkit-input-placeholder", AtomicString::ConstructFromLiteral));
         placeholder->setAttribute(idAttr, ShadowElementNames::placeholder());
+        placeholder->setInlineStyleProperty(CSSPropertyDisplay, isPlaceholderVisible() ? CSSValueBlock : CSSValueNone, true);

[esprehn, 2015/08/21 10:18:10]

Just call updatePlaceholderVisibility() here, no reason to copy this code.

[ramya.v, 2015/08/25 10:24:45]

updatePlaceholderText is called from inside updatePlaceholderVisibility() for
the first time when placeholder element is not present. If we add this, it would
become re-entrant.

         userAgentShadowRoot()->insertBefore(placeholder, innerEditorElement()->nextSibling());
     }
     placeholder->setTextContent(placeholderText);