Support implicit receiver in if-then intentions #KT-16069 Fixed

idea/testData/intentions/branched/ifThenToDoubleBang/this.kt

@@ -0,0 +1,2 @@
+// WITH_RUNTIME
+fun String?.foo() = if (this == <caret>null) throw NullPointerException() else this

idea/testData/intentions/branched/ifThenToDoubleBang/this.kt.after

@@ -0,0 +1,2 @@
+// WITH_RUNTIME
+fun String?.foo() = this!!

idea/testData/intentions/branched/ifThenToElvis/implicitReceiver.kt

@@ -0,0 +1,2 @@
+// WITH_RUNTIME
+fun String?.foo() = <caret>if (this == null) true else isEmpty()

idea/testData/intentions/branched/ifThenToElvis/implicitReceiver.kt.after

@@ -0,0 +1,2 @@
+// WITH_RUNTIME
+fun String?.foo() = this?.isEmpty() ?: true

idea/testData/intentions/branched/ifThenToElvis/inspectionData/expected.xml

@@ -95,4 +95,12 @@
     <problem_class severity="WARNING" attribute_key="WARNING_ATTRIBUTES">If-Then foldable to '?:'</problem_class>
     <description>Replace 'if' expression with elvis expression</description>
   </problem>
+  <problem>
+    <file>implicitReceiver.kt</file>
+    <line>2</line>
+    <module>light_idea_test_case</module>
+    <entry_point TYPE="file" FQNAME="temp:///src/implicitReceiver.kt" />
+    <problem_class severity="WARNING" attribute_key="WARNING_ATTRIBUTES">If-Then foldable to '?:'</problem_class>
+    <description>Replace 'if' expression with elvis expression</description>
+  </problem>
 </problems>

idea/testData/intentions/branched/ifThenToSafeAccess/implicitReceiver.kt

@@ -0,0 +1,2 @@
+// WITH_RUNTIME
+fun String?.foo() = <caret>if (this == null) null else isEmpty()

idea/testData/intentions/branched/ifThenToSafeAccess/implicitReceiver.kt.after

@@ -0,0 +1,2 @@
+// WITH_RUNTIME
+fun String?.foo() = this?.isEmpty()

idea/testData/intentions/branched/ifThenToSafeAccess/inspectionData/expected.xml

@@ -143,4 +143,12 @@
     <problem_class severity="WARNING" attribute_key="WARNING_ATTRIBUTES">If-Then foldable to '?.'</problem_class>
     <description>Remove redundant 'if' expression</description>
   </problem>
+  <problem>
+    <file>implicitReceiver.kt</file>
+    <line>2</line>
+    <module>light_idea_test_case</module>
+    <entry_point TYPE="file" FQNAME="temp:///src/implicitReceiver.kt" />
+    <problem_class severity="WARNING" attribute_key="WARNING_ATTRIBUTES">If-Then foldable to '?.'</problem_class>
+    <description>Remove redundant 'if' expression</description>
+  </problem>
 </problems>