Relax rules about inferring to Nothing for special calls

#KT-37388 Fixed
 #KT-38427 Fixed
 #KT-39953 Fixed
 #KT-38899 Fixed

compiler/frontend/src/org/jetbrains/kotlin/resolve/calls/DiagnosticReporterByTrackingStrategy.kt

@@ -178,7 +178,9 @@ class DiagnosticReporterByTrackingStrategy(
 
             ArgumentTypeMismatchDiagnostic::class.java -> {
                 require(diagnostic is ArgumentTypeMismatchDiagnostic)
-                val expression = callArgument.safeAs<PSIKotlinCallArgument>()?.valueArgument?.getArgumentExpression()
+                val expression = callArgument.safeAs<PSIKotlinCallArgument>()?.valueArgument?.getArgumentExpression()?.let {
+                    KtPsiUtil.deparenthesize(it) ?: it
+                }
                 if (expression != null) {
                     if (expression.isNull() && expression is KtConstantExpression) {
                         trace.reportDiagnosticOnce(NULL_FOR_NONNULL_TYPE.on(expression, diagnostic.expectedType))

compiler/frontend/src/org/jetbrains/kotlin/resolve/calls/smartcasts/DataFlowInfoImpl.kt

@@ -27,6 +27,7 @@ import org.jetbrains.kotlin.types.*
 import org.jetbrains.kotlin.types.checker.NewCapturedTypeConstructor
 import org.jetbrains.kotlin.types.typeUtil.contains
 import org.jetbrains.kotlin.types.typeUtil.isSubtypeOf
+import org.jetbrains.kotlin.types.typeUtil.makeNotNullable
 import org.jetbrains.kotlin.util.javaslang.*
 import org.jetbrains.kotlin.utils.newLinkedHashSetWithExpectedSize
 import java.util.*
@@ -302,9 +303,25 @@ internal class DataFlowInfoImpl private constructor(
         when {
             this == null -> other ?: ImmutableLinkedHashSet.empty()
             other == null -> this
-            else -> this.intersect(other)
+            else -> {
+                // Here we cover the case when "this" has T?!! type and "other" has T
+                val thisApproximated = approximateDefinitelyNotNullableTypes(this)
+                val otherApproximated = approximateDefinitelyNotNullableTypes(other)
+                if (thisApproximated == null && otherApproximated == null ||
+                    thisApproximated != null && otherApproximated != null
+                ) {
+                    this.intersect(other)
+                } else {
+                    (thisApproximated ?: this).intersect(otherApproximated ?: other)
+                }
+            }
         }
 
+    private fun approximateDefinitelyNotNullableTypes(set: ImmutableSet<KotlinType>): ImmutableSet<KotlinType>? {
+        if (!set.any { it.isDefinitelyNotNullType }) return null
+        return set.map { if (it is DefinitelyNotNullType) it.original.makeNotNullable() else it }
+    }
+
     override fun or(other: DataFlowInfo): DataFlowInfo {
         if (other === DataFlowInfo.EMPTY) return DataFlowInfo.EMPTY
         if (this === DataFlowInfo.EMPTY) return DataFlowInfo.EMPTY

compiler/frontend/src/org/jetbrains/kotlin/types/expressions/ControlStructureTypingUtils.java

@@ -177,8 +177,7 @@ public class ControlStructureTypingUtils {
             @NotNull KotlinType expectedType,
             @NotNull LanguageVersionSettings languageVersionSettings
     ) {
-        if (languageVersionSettings.supportsFeature(LanguageFeature.NewInference)
-            || construct == ResolveConstruct.ELVIS
+        if (construct == ResolveConstruct.ELVIS
             || TypeUtils.noExpectedType(expectedType)
             || TypeUtils.isDontCarePlaceholder(expectedType)
             || KotlinBuiltIns.isUnitOrNullableUnit(expectedType)