[JS IR BE] hashCode, toString, number conversion support

compiler/testData/codegen/box/ieee754/explicitCompareCall.kt

@@ -1,4 +1,3 @@
-// IGNORE_BACKEND: JS_IR
 fun less1(a: Double, b: Double) = a.compareTo(b) == -1
 
 fun less2(a: Double?, b: Double?) = a!!.compareTo(b!!) == -1

compiler/testData/codegen/box/ieee754/explicitEqualsCall.kt

@@ -1,4 +1,3 @@
-// IGNORE_BACKEND: JS_IR
 fun equals1(a: Double, b: Double) = a.equals(b)
 
 fun equals2(a: Double?, b: Double?) = a!!.equals(b!!)

compiler/testData/codegen/box/ieee754/safeCall.kt

@@ -1,4 +1,3 @@
-// IGNORE_BACKEND: JS_IR
 fun box(): String {
     val plusZero: Double? = 0.0
     val minusZero: Double = -0.0

compiler/testData/codegen/box/ieee754/smartCastToDifferentTypes_properIeeeComparisons.kt

@@ -1,5 +1,4 @@
 // !LANGUAGE: +ProperIeee754Comparisons
-// IGNORE_BACKEND: JS_IR
 
 fun ne(x: Any, y: Any) = x is Double && y is Float && x != y
 fun lt(x: Any, y: Any) = x is Double && y is Float && x < y