Make the compositing assert disabler for paint invalidation more targeted.

Source/core/editing/Caret.cpp

Index: Source/core/editing/Caret.cpp
diff --git a/Source/core/editing/Caret.cpp b/Source/core/editing/Caret.cpp
index 8bdff9f794466760c61ac8319b0d90b6e591da54..0471418756a9405398c9d4b9517b93278173b681 100644
--- a/Source/core/editing/Caret.cpp
+++ b/Source/core/editing/Caret.cpp
@@ -14,7 +14,7 @@
  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE COMPUTER, INC. OR
- * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
@@ -33,6 +33,7 @@
 #include "core/frame/Settings.h"
 #include "core/html/HTMLTextFormControlElement.h"
 #include "core/rendering/RenderBlock.h"
+#include "core/rendering/RenderLayer.h"
 #include "core/rendering/RenderView.h"
 #include "platform/graphics/GraphicsContext.h"
 
@@ -61,6 +62,10 @@ bool DragCaretController::isContentRichlyEditable() const
 
 void DragCaretController::setCaretPosition(const VisiblePosition& position)
 {
+    // for querying RenderLayer::compositingState()
+    // This code is probably correct, since it doesn't occur in a stack that involves updating compositing state.
+    DisableCompositingQueryAsserts disabler;
+
     if (Node* node = m_position.deepEquivalent().deprecatedNode())
         invalidateCaretRect(node);
     m_position = position;