Minor cleanup: prefer actual body with return statement

compiler/fir/checkers/src/org/jetbrains/kotlin/fir/analysis/FirSourceChild.kt

@@ -9,14 +9,16 @@ import com.intellij.psi.tree.IElementType
 import com.intellij.psi.tree.TokenSet
 import org.jetbrains.kotlin.fir.*
 
-fun FirSourceElement.getChild(type: IElementType, index: Int = 0, depth: Int = -1): FirSourceElement? =
-    getChild(setOf(type), index, depth)
+fun FirSourceElement.getChild(type: IElementType, index: Int = 0, depth: Int = -1): FirSourceElement? {
+    return getChild(setOf(type), index, depth)
+}
 
-fun FirSourceElement.getChild(types: TokenSet, index: Int = 0, depth: Int = -1): FirSourceElement? =
-    getChild(types.types.toSet(), index, depth)
+fun FirSourceElement.getChild(types: TokenSet, index: Int = 0, depth: Int = -1): FirSourceElement? {
+    return getChild(types.types.toSet(), index, depth)
+}
 
-fun FirSourceElement.getChild(types: Set<IElementType>, index: Int = 0, depth: Int = -1): FirSourceElement? =
-    when (this) {
+fun FirSourceElement.getChild(types: Set<IElementType>, index: Int = 0, depth: Int = -1): FirSourceElement? {
+    return when (this) {
         is FirPsiSourceElement<*> -> {
             getChild(types, index, depth)
         }
@@ -25,6 +27,7 @@ fun FirSourceElement.getChild(types: Set<IElementType>, index: Int = 0, depth: I
         }
         else -> null
     }
+}
 
 private fun FirPsiSourceElement<*>.getChild(types: Set<IElementType>, index: Int, depth: Int): FirSourceElement? {
     val visitor = PsiElementFinderByType(types, index, depth)

compiler/fir/checkers/src/org/jetbrains/kotlin/fir/analysis/checkers/declaration/FirDeclarationCheckerUtils.kt

@@ -19,20 +19,23 @@ import org.jetbrains.kotlin.fir.declarations.impl.FirDefaultPropertyAccessor
 import org.jetbrains.kotlin.fir.types.FirImplicitTypeRef
 import org.jetbrains.kotlin.lexer.KtTokens
 
-internal fun isInsideExpectClass(containingClass: FirRegularClass, context: CheckerContext): Boolean =
-    isInsideSpecificClass(containingClass, context) { klass -> klass.isExpect }
+internal fun isInsideExpectClass(containingClass: FirRegularClass, context: CheckerContext): Boolean {
+    return isInsideSpecificClass(containingClass, context) { klass -> klass.isExpect }
+}
 
-internal fun isInsideExternalClass(containingClass: FirRegularClass, context: CheckerContext): Boolean =
-    isInsideSpecificClass(containingClass, context) { klass -> klass.isExternal }
+internal fun isInsideExternalClass(containingClass: FirRegularClass, context: CheckerContext): Boolean {
+    return isInsideSpecificClass(containingClass, context) { klass -> klass.isExternal }
+}
 
 // Note that the class that contains the currently visiting declaration will *not* be in the context's containing declarations *yet*.
 private inline fun isInsideSpecificClass(
     containingClass: FirRegularClass,
     context: CheckerContext,
     predicate: (FirRegularClass) -> Boolean
-): Boolean =
-    predicate.invoke(containingClass) ||
+): Boolean {
+    return predicate.invoke(containingClass) ||
             context.containingDeclarations.asReversed().any { it is FirRegularClass && predicate.invoke(it) }
+}
 
 internal fun FirMemberDeclaration.isEffectivelyExpect(
     containingClass: FirRegularClass?,