[IR] More extensive LVT tests around destructuring

All tests in this commit _pass_ to document existing behavior, but
this will change in a separate commit as we reflect desired behavior
in the test expectations.

compiler/testData/debug/localVariables/assignment.kt

@@ -0,0 +1,32 @@
+
+
+// FILE: test.kt
+fun box(): String {
+    val
+            o
+            =
+        "O"
+
+
+    val k = "K"
+
+    return o + k
+}
+
+// A location for the expression being evaluated, and one for the store to the LV, but:
+//    JVM: location for evaluating expression, location for the assigned variable
+//    JVM_IR: location for evaluating expression, location for the val keyword
+
+// EXPECTATIONS
+
+// EXPECTATIONS JVM
+// test.kt:8 box:
+// test.kt:6 box:
+// test.kt:11 box: o:java.lang.String="O":java.lang.String
+// test.kt:13 box: o:java.lang.String="O":java.lang.String, k:java.lang.String="K":java.lang.String
+
+// EXPECTATIONS JVM_IR
+// test.kt:8 box:
+// test.kt:5 box:
+// test.kt:11 box: o:java.lang.String="O":java.lang.String
+// test.kt:13 box: o:java.lang.String="O":java.lang.String, k:java.lang.String="K":java.lang.String