LineIndentProvider: support elvis operator

Part of #KT-22211

idea/testData/indentationOnNewline/elvis/AfterElvis.after.inv.kt

@@ -0,0 +1,6 @@
+fun test(some: Any?, error: Int) {
+    val test = some ?:
+    <caret>error
+}
+
+// SET_FALSE: CONTINUATION_INDENT_IN_ELVIS

idea/testData/indentationOnNewline/elvis/AfterElvis.after.kt

@@ -0,0 +1,6 @@
+fun test(some: Any?, error: Int) {
+    val test = some ?:
+    <caret>error
+}
+
+// SET_FALSE: CONTINUATION_INDENT_IN_ELVIS

idea/testData/indentationOnNewline/elvis/AfterElvis.kt

@@ -0,0 +1,5 @@
+fun test(some: Any?, error: Int) {
+    val test = some ?:<caret> error
+}
+
+// SET_FALSE: CONTINUATION_INDENT_IN_ELVIS

idea/testData/indentationOnNewline/elvis/AfterElvis2.after.inv.kt

@@ -0,0 +1,8 @@
+fun test(some: Any?, error: Int) {
+    some?.let {
+        println(some)
+    } ?:
+    <caret>println(error)
+}
+
+// SET_FALSE: CONTINUATION_INDENT_IN_ELVIS

idea/testData/indentationOnNewline/elvis/AfterElvis2.after.kt

@@ -0,0 +1,8 @@
+fun test(some: Any?, error: Int) {
+    some?.let {
+        println(some)
+    } ?:
+    <caret>println(error)
+}
+
+// SET_FALSE: CONTINUATION_INDENT_IN_ELVIS

idea/testData/indentationOnNewline/elvis/AfterElvis2.kt

@@ -0,0 +1,7 @@
+fun test(some: Any?, error: Int) {
+    some?.let {
+        println(some)
+    } ?: <caret>println(error)
+}
+
+// SET_FALSE: CONTINUATION_INDENT_IN_ELVIS

idea/testData/indentationOnNewline/elvis/AfterElvisInBinaryExpression.after.inv.kt

@@ -0,0 +1,6 @@
+fun a() {
+    println(1 + null ?:
+    <caret>2)
+}
+
+// SET_FALSE: CONTINUATION_INDENT_IN_ELVIS

idea/testData/indentationOnNewline/elvis/AfterElvisInBinaryExpression.after.kt

@@ -0,0 +1,6 @@
+fun a() {
+    println(1 + null ?:
+    <caret>2)
+}
+
+// SET_FALSE: CONTINUATION_INDENT_IN_ELVIS

idea/testData/indentationOnNewline/elvis/AfterElvisInBinaryExpression.kt

@@ -0,0 +1,5 @@
+fun a() {
+    println(1 + null ?: <caret>2)
+}
+
+// SET_FALSE: CONTINUATION_INDENT_IN_ELVIS

idea/testData/indentationOnNewline/elvis/BeforeElvis.after.inv.kt

@@ -0,0 +1,6 @@
+fun test(some: Any?, error: Int) {
+    val test = some
+            <caret>?: error
+}
+
+// SET_FALSE: CONTINUATION_INDENT_IN_ELVIS

idea/testData/indentationOnNewline/elvis/BeforeElvis.after.kt

@@ -0,0 +1,6 @@
+fun test(some: Any?, error: Int) {
+    val test = some
+        <caret>?: error
+}
+
+// SET_FALSE: CONTINUATION_INDENT_IN_ELVIS

idea/testData/indentationOnNewline/elvis/BeforeElvis.kt

@@ -0,0 +1,5 @@
+fun test(some: Any?, error: Int) {
+    val test = some <caret>?: error
+}
+
+// SET_FALSE: CONTINUATION_INDENT_IN_ELVIS

idea/testData/indentationOnNewline/elvis/BeforeElvisInBinaryExpression.after.inv.kt

@@ -0,0 +1,6 @@
+fun a() {
+    println(1 + null
+            <caret>?: 2)
+}
+
+// SET_FALSE: CONTINUATION_INDENT_IN_ELVIS

idea/testData/indentationOnNewline/elvis/BeforeElvisInBinaryExpression.after.kt

@@ -0,0 +1,6 @@
+fun a() {
+    println(1 + null
+        <caret>?: 2)
+}
+
+// SET_FALSE: CONTINUATION_INDENT_IN_ELVIS

idea/testData/indentationOnNewline/elvis/BeforeElvisInBinaryExpression.kt

@@ -0,0 +1,5 @@
+fun a() {
+    println(1 + null <caret>?: 2)
+}
+
+// SET_FALSE: CONTINUATION_INDENT_IN_ELVIS