StreamApiMigration: add parentheses if necessary when .stream() can be omitted (fix for EA-93812).

java/java-impl/src/com/intellij/codeInspection/streamMigration/TerminalBlock.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2000-2016 JetBrains s.r.o.
+ * Copyright 2000-2017 JetBrains s.r.o.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -447,7 +447,7 @@ class TerminalBlock {
 
   String generate(boolean noStreamForEmpty) {
     if(noStreamForEmpty && myOperations.length == 1 && myOperations[0] instanceof CollectionStream) {
-      return myOperations[0].getExpression().getText();
+      return ParenthesesUtils.getText(myOperations[0].getExpression(), ParenthesesUtils.POSTFIX_PRECEDENCE);
     }
     return StreamEx.of(myOperations).map(Operation::createReplacement).joining();
   }

java/java-tests/testData/codeInsight/daemonCodeAnalyzer/quickFix/streamApiMigration/afterForEachCast.java

@@ -0,0 +1,9 @@
+// "Replace with forEach" "true"
+
+import java.util.Collection;
+
+public class Test {
+  void test(Object obj) {
+      ((Collection<String>) obj).forEach(System.out::println);
+  }
+}

java/java-tests/testData/codeInsight/daemonCodeAnalyzer/quickFix/streamApiMigration/beforeForEachCast.java

@@ -0,0 +1,11 @@
+// "Replace with forEach" "true"
+
+import java.util.Collection;
+
+public class Test {
+  void test(Object obj) {
+    for(String str : (Collection<String>)<caret>obj) {
+      System.out.println(str);
+    }
+  }
+}