generate "constant".equals(variable) code when converting switch to if (IDEA-157516)

java/java-tests/testData/codeInsight/daemonCodeAnalyzer/quickFix/convertSwitchToIf/afterString.java

@@ -0,0 +1,9 @@
+// "Replace 'switch' with 'if'" "true"
+class X {
+  public void doSomething( String value) {
+      if ("case1".equals(value)) {
+      } else if ("case2".equals(value)) {
+      } else {
+      }
+  }
+}