Fix error plumbing in WorkItem

pkg/analyzer/lib/src/task/driver.dart

Index: pkg/analyzer/lib/src/task/driver.dart
diff --git a/pkg/analyzer/lib/src/task/driver.dart b/pkg/analyzer/lib/src/task/driver.dart
index 0f3b523435d941f418f24c1c50bd56766d4ce2b5..a041729d53e56ee3711d044f40ffe6a445942d19 100644
--- a/pkg/analyzer/lib/src/task/driver.dart
+++ b/pkg/analyzer/lib/src/task/driver.dart
@@ -722,11 +722,10 @@ class WorkItem {
             this.exception = new CaughtException(exception, stackTrace);
             return null;
           } catch (exception, stackTrace) {
-            this.exception = new CaughtException(
-                throw new AnalysisException(
-                    'Cannot create work order to build $inputResult for $inputTarget',
-                    exception),
-                stackTrace);
+            this.exception = new CaughtException(exception, stackTrace);
+            throw new AnalysisException(
+                'Cannot create work order to build $inputResult for $inputTarget',
+                this.exception);
             return null;
           }
         }