InvertIfCondition: some fixes for non-compilable code

java/java-tests/testData/codeInsight/invertIfCondition/afterEmptyParenthesis.java

@@ -0,0 +1,11 @@
+// "Invert 'if' condition" "true"
+class A {
+    public boolean foo() {
+        if (!()) {
+            return true;
+        }
+        else {
+            return false;
+        }
+    }
+}

java/java-tests/testData/codeInsight/invertIfCondition/afterNull.java

@@ -0,0 +1,11 @@
+// "Invert 'if' condition" "true"
+class A {
+    public boolean foo() {
+        if (!null) {
+            return true;
+        }
+        else {
+            return false;
+        }
+    }
+}

java/java-tests/testData/codeInsight/invertIfCondition/beforeEmptyParenthesis.java

@@ -0,0 +1,9 @@
+// "Invert 'if' condition" "true"
+class A {
+    public boolean foo() {
+      if ((<caret>))
+        return false;
+      else
+        return true;
+    }
+}

java/java-tests/testData/codeInsight/invertIfCondition/beforeNull.java

@@ -0,0 +1,9 @@
+// "Invert 'if' condition" "true"
+class A {
+    public boolean foo() {
+      if (n<caret>ull)
+        return false;
+      else
+        return true;
+    }
+}