Devtools: Margin resizer in overlay experiment

Source/web/InspectorOverlayImpl.cpp

Index: Source/web/InspectorOverlayImpl.cpp
diff --git a/Source/web/InspectorOverlayImpl.cpp b/Source/web/InspectorOverlayImpl.cpp
index 4505ea256c05f260c36c16bb24c26a762001bdcb..abe2c24cbf28e067ea9be269c29d3367d5b7a4ed 100644
--- a/Source/web/InspectorOverlayImpl.cpp
+++ b/Source/web/InspectorOverlayImpl.cpp
@@ -42,6 +42,7 @@
 #include "core/page/ChromeClient.h"
 #include "core/page/EventHandler.h"
 #include "core/page/Page.h"
+#include "core/style/ComputedStyle.h"
 #include "platform/JSONValues.h"
 #include "platform/ScriptForbiddenScope.h"
 #include "platform/graphics/GraphicsContext.h"
@@ -105,6 +106,7 @@ public:
     void highlightQuad(PassOwnPtr<FloatQuad>, const InspectorHighlightConfig&) override { }
     void showAndHideViewSize(bool showGrid) override { }
     void setListener(InspectorOverlay::Listener* listener) override { }
+    void setCSSListener(InspectorOverlay::CSSListener* listener) override { }
     void suspendUpdates() override { }
     void resumeUpdates() override { }
     void clear() override { }
@@ -135,6 +137,7 @@ InspectorOverlayImpl::InspectorOverlayImpl(WebViewImpl* webViewImpl)
     , m_updating(false)
 {
     m_overlayHost->setListener(this);
+    m_overlayHost->setCSSListener(this);
 }
 
 InspectorOverlayImpl::~InspectorOverlayImpl()
@@ -232,6 +235,9 @@ void InspectorOverlayImpl::highlightNode(Node* node, Node* eventTarget, const In
     m_highlightNode = node;
     m_eventTargetNode = eventTarget;
     m_omitTooltip = omitTooltip;
+    const ComputedStyle* style = m_highlightNode->computedStyle();
+    if (style)
+        m_initValue = style->marginLeft().intValue();
     update();
 }
 
@@ -461,6 +467,14 @@ void InspectorOverlayImpl::overlaySteppedOver()
         m_listener->overlaySteppedOver();
 }
 
+void InspectorOverlayImpl::updateCSSProperty(long newValue)
+{
+
+    if (!m_cssListener || !m_highlightNode)
+        return;
+    m_cssListener->updateCSSProperty(m_highlightNode.get(), m_initValue + newValue);
+}
+
 void InspectorOverlayImpl::suspendUpdates()
 {
     if (!m_suspendCount++)