IDEA-122974 expected type suggester should ignore 'null' types

java/java-impl/src/com/intellij/codeInsight/ExpectedTypesProvider.java

@@ -495,7 +495,7 @@ public class ExpectedTypesProvider {
         PsiExpression rExpr = assignment.getRExpression();
         if (rExpr != null) {
           PsiType type = rExpr.getType();
-          if (type != null) {
+          if (type != null && type != PsiType.NULL) {
             if (type instanceof PsiClassType) {
               final PsiClass resolved = ((PsiClassType)type).resolve();
               if (resolved instanceof PsiAnonymousClass) {

java/java-tests/testData/codeInsight/daemonCodeAnalyzer/quickFix/createLocalFromUsage/afterNull.java

@@ -0,0 +1,9 @@
+// "Create Local Variable 'str'" "true"
+public class A {
+    void foo() {
+        String str;
+        String s = str;
+        str = null;
+    }
+
+}

java/java-tests/testData/codeInsight/daemonCodeAnalyzer/quickFix/createLocalFromUsage/beforeNull.java

@@ -0,0 +1,8 @@
+// "Create Local Variable 'str'" "true"
+public class A {
+    void foo() {
+        String s = s<caret>tr;
+        str = null;
+    }
+
+}