Clean-up use lambdas and method references on
bundles/org.eclipse.e4.ui.css.core

Using the JDT cleanup action -> Use lambda where possible
Simplify lambda expression and method reference syntax

Change-Id: I99b3e3db59c3d336b04c28a1a03f9d319b37d983
Signed-off-by: Lars Vogel <Lars.Vogel@vogella.com>
diff --git a/bundles/org.eclipse.e4.ui.css.core/src/org/eclipse/e4/ui/css/core/impl/engine/AbstractCSSEngine.java b/bundles/org.eclipse.e4.ui.css.core/src/org/eclipse/e4/ui/css/core/impl/engine/AbstractCSSEngine.java
index 4e8d9cc..443ecdc 100644
--- a/bundles/org.eclipse.e4.ui.css.core/src/org/eclipse/e4/ui/css/core/impl/engine/AbstractCSSEngine.java
+++ b/bundles/org.eclipse.e4.ui.css.core/src/org/eclipse/e4/ui/css/core/impl/engine/AbstractCSSEngine.java
@@ -560,7 +560,7 @@
 					switch (handlers2.size()) {
 					case 0:
 						handlers2 = propertyHandler2InstanceMap.computeIfAbsent(propertyHandler2,
-								h -> Collections.singletonList(h));
+								Collections::singletonList);
 						break;
 					case 1:
 						handlers2 = new ArrayList<>(handlers2);
diff --git a/bundles/org.eclipse.e4.ui.css.core/src/org/eclipse/e4/ui/css/core/impl/engine/RegistryCSSPropertyHandlerProvider.java b/bundles/org.eclipse.e4.ui.css.core/src/org/eclipse/e4/ui/css/core/impl/engine/RegistryCSSPropertyHandlerProvider.java
index 0b22932..c75df77 100644
--- a/bundles/org.eclipse.e4.ui.css.core/src/org/eclipse/e4/ui/css/core/impl/engine/RegistryCSSPropertyHandlerProvider.java
+++ b/bundles/org.eclipse.e4.ui.css.core/src/org/eclipse/e4/ui/css/core/impl/engine/RegistryCSSPropertyHandlerProvider.java
@@ -193,7 +193,7 @@
 					switch (handlers.size()) {
 					case 0:
 						handlers = propertyHandlerInstanceMap.computeIfAbsent(handler,
-								h -> Collections.singletonList(h));
+								Collections::singletonList);
 						break;
 					case 1:
 						handlers = new ArrayList<>(handlers);