DevTools: remove unused parts of the CSS instrumentation.

Source/core/css/PropertySetCSSStyleDeclaration.cpp

Index: Source/core/css/PropertySetCSSStyleDeclaration.cpp
diff --git a/Source/core/css/PropertySetCSSStyleDeclaration.cpp b/Source/core/css/PropertySetCSSStyleDeclaration.cpp
index 7b7e1423bf0b1537aa3ec49ed1df5b9b450f4891..007331b3017e341c2a7b9466a65dddd0d5caad8d 100644
--- a/Source/core/css/PropertySetCSSStyleDeclaration.cpp
+++ b/Source/core/css/PropertySetCSSStyleDeclaration.cpp
@@ -44,7 +44,6 @@ class StyleAttributeMutationScope {
 public:
     StyleAttributeMutationScope(AbstractPropertySetCSSStyleDeclaration* decl)
     {
-        InspectorInstrumentation::willMutateStyle(decl);
         ++s_scopeCount;
 
         if (s_scopeCount != 1) {
@@ -88,7 +87,6 @@ public:
         // We have to clear internal state before calling Inspector's code.
         AbstractPropertySetCSSStyleDeclaration* localCopyStyleDecl = s_currentDecl;
         s_currentDecl = 0;
-        InspectorInstrumentation::didMutateStyle(localCopyStyleDecl, localCopyStyleDecl->parentElement());
 
         if (!s_shouldNotifyInspector)
             return;