vaadin-framework/client/src/com/vaadin/VaadinBrowserSpecificOverrides.gwt.xml

<module>
	<!-- This GWT module defines the browser specific overrides used by Vaadin -->

	<!-- Hint for WidgetSetBuilder not to automatically update the file -->
	<!-- WS Compiler: manually edited -->

	<!-- Fall through to this rule for everything but IE -->
	<replace-with
		class="com.vaadin.client.ui.upload.UploadIFrameOnloadStrategy">
		<when-type-is
			class="com.vaadin.client.ui.upload.UploadIFrameOnloadStrategy" />
	</replace-with>

	<replace-with
		class="com.vaadin.client.ui.upload.UploadIFrameOnloadStrategyIE">
		<when-type-is
			class="com.vaadin.client.ui.upload.UploadIFrameOnloadStrategy" />
		<any>
			<when-property-is name="user.agent" value="ie8" />
		</any>
	</replace-with>

	<!-- Fall through to this rule for everything but IE -->
	<replace-with class="com.vaadin.client.ui.draganddropwrapper.VDragAndDropWrapper">
		<when-type-is class="com.vaadin.client.ui.draganddropwrapper.VDragAndDropWrapper" />
	</replace-with>

	<replace-with class="com.vaadin.client.ui.draganddropwrapper.VDragAndDropWrapperIE">
		<when-type-is class="com.vaadin.client.ui.draganddropwrapper.VDragAndDropWrapper" />
		<any>
			<when-property-is name="user.agent" value="ie8" />
		</any>
	</replace-with>

	<!-- Fall through to this rule for everything but IE -->
	<replace-with class="com.vaadin.client.LayoutManager">
		<when-type-is class="com.vaadin.client.LayoutManager" />
	</replace-with>

	<replace-with class="com.vaadin.client.LayoutManagerIE8">
		<when-type-is class="com.vaadin.client.LayoutManager" />
		<any>
			<when-property-is name="user.agent" value="ie8" />
		</any>
	</replace-with>

</module>