Lift assignment out: do not report when assignment variables are different

#KT-38649 Fixed

idea/src/org/jetbrains/kotlin/idea/intentions/branchedTransformations/BranchedFoldingUtils.kt

@@ -21,6 +21,7 @@ import org.jetbrains.kotlin.diagnostics.Errors
 import org.jetbrains.kotlin.idea.caches.resolve.analyze
 import org.jetbrains.kotlin.idea.core.replaced
 import org.jetbrains.kotlin.idea.intentions.branches
+import org.jetbrains.kotlin.idea.references.mainReference
 import org.jetbrains.kotlin.lexer.KtTokens
 import org.jetbrains.kotlin.psi.*
 import org.jetbrains.kotlin.psi.psiUtil.anyDescendantOfType
@@ -66,7 +67,9 @@ object BranchedFoldingUtils {
     ): Boolean {
         val left = this.left ?: return false
         val otherLeft = other.left ?: return false
-        if (left.text != otherLeft.text || operationToken != other.operationToken) return false
+        if (left.text != otherLeft.text || operationToken != other.operationToken ||
+            left.mainReference?.resolve() != otherLeft.mainReference?.resolve()
+        ) return false
         val rightType = other.rightType() ?: return false
         return rightType.constructor == rightTypeConstructor || (operationToken == KtTokens.EQ && rightType.isSubtypeOf(leftType))
     }

idea/testData/inspectionsLocal/liftOut/whenToAssignment/differentVariablesWithSame.kt

@@ -0,0 +1,18 @@
+// PROBLEM: none
+// WITH_RUNTIME
+
+class A {
+    val list: MutableList<String> = mutableListOf()
+}
+
+class B {
+    val list: MutableList<String> = mutableListOf()
+}
+
+fun Any.add(s: String) {
+    <caret>when (this) {
+        is A -> list += s
+        is B -> list += s
+        else -> throw IllegalStateException()
+    }
+}

idea/tests/org/jetbrains/kotlin/idea/inspections/LocalInspectionTestGenerated.java

@@ -5707,6 +5707,11 @@ public class LocalInspectionTestGenerated extends AbstractLocalInspectionTest {
                 runTest("idea/testData/inspectionsLocal/liftOut/whenToAssignment/cascadeWhen.kt");
             }
 
+            @TestMetadata("differentVariablesWithSame.kt")
+            public void testDifferentVariablesWithSame() throws Exception {
+                runTest("idea/testData/inspectionsLocal/liftOut/whenToAssignment/differentVariablesWithSame.kt");
+            }
+
             @TestMetadata("innerWhenTransformed.kt")
             public void testInnerWhenTransformed() throws Exception {
                 runTest("idea/testData/inspectionsLocal/liftOut/whenToAssignment/innerWhenTransformed.kt");