extract method: check duplicates/used vars also in unreachable code

(cherry picked from commit 42249fe8f0cead1a0023aa9edfb23fc52a95c268)

java/java-analysis-impl/src/com/intellij/refactoring/util/duplicates/Match.java

@@ -282,7 +282,7 @@ public final class Match {
     try {
       final Project project = getMatchStart().getProject();
       final ControlFlow controlFlow = ControlFlowFactory.getInstance(project)
-          .getControlFlow(codeFragment, new LocalsControlFlowPolicy(codeFragment));
+          .getControlFlow(codeFragment, new LocalsControlFlowPolicy(codeFragment), false, false);
       final int endOffset = controlFlow.getEndOffset(getMatchEnd());
       final int startOffset = controlFlow.getStartOffset(getMatchStart());
       final List<PsiVariable> usedVariables = ControlFlowUtil.getUsedVariables(controlFlow, endOffset, controlFlow.getSize());

java/java-impl/src/com/intellij/refactoring/extractMethodObject/ExtractLightMethodObjectHandler.java

@@ -150,7 +150,7 @@ public class ExtractLightMethodObjectHandler {
 
     final ControlFlow controlFlow;
     try {
-      controlFlow = ControlFlowFactory.getInstance(project).getControlFlow(container, LocalsOrMyInstanceFieldsControlFlowPolicy.getInstance());
+      controlFlow = ControlFlowFactory.getInstance(project).getControlFlow(container, LocalsOrMyInstanceFieldsControlFlowPolicy.getInstance(), false, false);
     }
     catch (AnalysisCanceledException e) {
       return null;

java/java-tests/testData/refactoring/extractMethod/DuplicateInUnreachableCode.java

@@ -0,0 +1,16 @@
+
+class A {
+  private static final boolean ourOverrideFinalFields = false;
+
+  public static String createShared(char[] chars) {
+
+    if (ourOverrideFinalFields) {
+      String s = new String();
+      return s;
+    }
+    String s = <selection>new String()</selection>;
+    return new String(chars);
+  }
+
+
+}

java/java-tests/testData/refactoring/extractMethod/DuplicateInUnreachableCode_after.java

@@ -0,0 +1,22 @@
+import org.jetbrains.annotations.NotNull;
+
+class A {
+  private static final boolean ourOverrideFinalFields = false;
+
+  public static String createShared(char[] chars) {
+
+    if (ourOverrideFinalFields) {
+      String s = newMethod();
+      return s;
+    }
+    String s = newMethod();
+    return new String(chars);
+  }
+
+    @NotNull
+    private static String newMethod() {
+        return new String();
+    }
+
+
+}

java/java-tests/testSrc/com/intellij/refactoring/ExtractMethodTest.java

@@ -233,6 +233,10 @@ public class ExtractMethodTest extends LightCodeInsightTestCase {
     doDuplicatesTest();
   }
 
+  public void testDuplicateInUnreachableCode() throws Exception {
+    doDuplicatesTest();
+  }
+
   public void testExpressionDuplicates() throws Exception {
     doDuplicatesTest();
   }