qmljs: fix unreachable test for catch clause

Change-Id: Ica1ff034b88f06849026957c8beed2cda77badcc
Reviewed-by: Christian Stenger <christian.stenger@qt.io>
Reviewed-by: Fabian Kosmale <fabian.kosmale@qt.io>

src/libs/qmljs/qmljscheck.cpp

@@ -502,13 +502,13 @@ protected:
         return false;
     }
 
-    bool visit(Block *) override
+    bool openBlock()
     {
         ++_block;
         return true;
     }
 
-    void endVisit(Block *) override
+    void closeBlock()
     {
         auto it = _declaredBlockVariables.begin();
         auto end = _declaredBlockVariables.end();
@@ -521,6 +521,26 @@ protected:
         --_block;
     }
 
+    bool visit(Block *) override
+    {
+        return openBlock();
+    }
+
+    void endVisit(Block *) override
+    {
+        closeBlock();
+    }
+
+    bool visit(Catch *) override
+    {
+        return openBlock();
+    }
+
+    void endVisit(Catch *) override
+    {
+        closeBlock();
+    }
+
     void throwRecursionDepthError() override
     {
         addMessage(ErrHitMaximumRecursion, SourceLocation());