IDEA-161462 Password settings: misaligned button

platform/credential-store/src/PasswordSafeConfigurable.kt

@@ -57,15 +57,14 @@ class PasswordSafeConfigurableUi : ConfigurableUi<PasswordSafeSettings> {
       row { rememberPasswordsUntilClosing() }
     }
 
-    if (!passwordSafe.isNativeCredentialStoreUsed)
-      row {
-        right {
-          button("Clear Passwords") { event ->
-            passwordSafe.clearPasswords()
-            Messages.showInfoMessage(event.source as Component, "Passwords were cleared", "Clear Passwords")
-          }
+    if (!passwordSafe.isNativeCredentialStoreUsed) {
+      row(separated = true) {
+        button("Clear Passwords") { event ->
+          passwordSafe.clearPasswords()
+          Messages.showInfoMessage(event.source as Component, "Passwords were cleared", "Clear Passwords")
         }
       }
+    }
   }
 
   private fun getProviderType(): ProviderType {

platform/platform-impl/src/com/intellij/ui/layout/LayoutBuilder.kt

@@ -21,11 +21,11 @@ import javax.swing.JLabel
 
 class LayoutBuilder(val `$`: LayoutBuilderImpl, val buttonGroup: ButtonGroup? = null) {
   inline fun row(label: String, init: Row.() -> Unit) {
-    row(Label(label), init)
+    row(label = Label(label), init = init)
   }
 
-  inline fun row(label: JLabel? = null, init: Row.() -> Unit) {
-    `$`.newRow(label, buttonGroup).init()
+  inline fun row(label: JLabel? = null, separated: Boolean = false, init: Row.() -> Unit) {
+    `$`.newRow(label, buttonGroup, separated).init()
   }
 
   /**

platform/platform-impl/src/com/intellij/ui/layout/MigLayoutBuilder.kt

@@ -20,6 +20,8 @@ import com.intellij.openapi.actionSystem.ActionToolbar
 import com.intellij.openapi.actionSystem.AnActionEvent
 import com.intellij.openapi.actionSystem.ToggleAction
 import com.intellij.openapi.project.DumbAware
+import com.intellij.openapi.ui.OnePixelDivider
+import com.intellij.ui.SeparatorComponent
 import com.intellij.ui.components.noteComponent
 import com.intellij.util.SmartList
 import net.miginfocom.layout.*
@@ -38,7 +40,13 @@ internal class MigLayoutBuilder : LayoutBuilderImpl {
 
   private val componentConstraints: MutableMap<Component, CC> = SmartHashMap()
 
-  override fun newRow(label: JLabel?, buttonGroup: ButtonGroup?): Row {
+  override fun newRow(label: JLabel?, buttonGroup: ButtonGroup?, separated: Boolean): Row {
+    if (separated) {
+      val row = MigLayoutRow(componentConstraints, noGrid = true, separated = true)
+      rows.add(row)
+      row.apply { SeparatorComponent(0, OnePixelDivider.BACKGROUND, null)() }
+    }
+
     val row = MigLayoutRow(componentConstraints, label != null, buttonGroup = buttonGroup)
     rows.add(row)
 
@@ -48,7 +56,7 @@ internal class MigLayoutBuilder : LayoutBuilderImpl {
   }
 
   override fun noteRow(text: String) {
-    // add empty row
+    // add empty row as top gap
     newRow()
 
     val row = MigLayoutRow(componentConstraints, noGrid = true)
@@ -106,6 +114,10 @@ internal class MigLayoutBuilder : LayoutBuilderImpl {
             if (component === row.components.first()) {
               // rowConstraints.noGrid() doesn't work correctly
               cc.spanX()
+              if (row.separated) {
+                cc.vertical.gapBefore = gapToBoundSize(VERTICAL_GAP * 3, false)
+                cc.vertical.gapAfter = gapToBoundSize(VERTICAL_GAP * 2, false)
+              }
             }
           }
           else {
@@ -135,7 +147,7 @@ internal class MigLayoutBuilder : LayoutBuilderImpl {
 }
 
 private fun addGrowIfNeed(cc: CC, component: Component) {
-  if (component is JTextComponent) {
+  if (component is JTextComponent || component is SeparatorComponent) {
     cc.growX()
   }
   else if (component is JPanel && component.componentCount == 1 &&
@@ -144,7 +156,7 @@ private fun addGrowIfNeed(cc: CC, component: Component) {
   }
 }
 
-private class MigLayoutRow(private val componentConstraints: MutableMap<Component, CC>, val labeled: Boolean = false, val noGrid: Boolean = false, private val buttonGroup: ButtonGroup? = null) : Row() {
+private class MigLayoutRow(private val componentConstraints: MutableMap<Component, CC>, val labeled: Boolean = false, val noGrid: Boolean = false, private val buttonGroup: ButtonGroup? = null, val separated: Boolean = false) : Row() {
   val components = SmartList<Component>()
   var rightIndex = Int.MAX_VALUE
 

platform/platform-impl/src/com/intellij/ui/layout/layoutImpl.kt

@@ -32,7 +32,7 @@ fun createLayoutBuilder() = LayoutBuilder(MigLayoutBuilder())
 // "When a protected member is accessed from an inline function, a public accessor method is created to provide an access to that protected member from the outside of the class where the function will be inlined to."
 // (https://youtrack.jetbrains.com/issue/KT-12215)
 interface LayoutBuilderImpl {
-  fun newRow(label: JLabel? = null, buttonGroup: ButtonGroup? = null): Row
+  fun newRow(label: JLabel? = null, buttonGroup: ButtonGroup? = null, separated: Boolean = false): Row
 
   fun build(container: Container, layoutConstraints: Array<out LCFlags>)