Bug 511836 - decrement counter also in case of exception

Change-Id: Ia9c3d4cc44a04579a5102a2eea6279fe89358fdd
Signed-off-by: Daniel Raap <raap@subshell.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 8012fa1..74e0a58 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
@@ -221,8 +221,11 @@
 				tempStream.setURI(url.toString());
 				tempStream.setByteStream(stream);
 				parseImport++;
-				styleSheet = (CSSStyleSheet) this.parseStyleSheet(tempStream);
-				parseImport--;
+				try {
+					styleSheet = (CSSStyleSheet) this.parseStyleSheet(tempStream);
+				} finally {
+					parseImport--;
+				}
 				CSSRuleList tempRules = styleSheet.getCssRules();
 				for (int j = 0; j < tempRules.getLength(); j++) {
 					masterList.add(tempRules.item(j));