Prohibit from eliminating non-local temporary variables

js/js.tests/test/org/jetbrains/kotlin/js/test/optimizer/TemporaryAssignmentEliminationTest.kt

@@ -24,4 +24,6 @@ class TemporaryAssignmentEliminationTest : BasicOptimizerTest("temporary-assignm
     @Test fun returnStatement() = box()
 
     @Test fun declaration() = box()
+
+    @Test fun skipsGlobalDeclarations() = box()
 }

js/js.tests/test/org/jetbrains/kotlin/js/test/optimizer/TemporaryVariableEliminationTest.kt

@@ -22,4 +22,6 @@ class TemporaryVariableEliminationTest : BasicOptimizerTest("temporary-variable"
     @Test fun declaration() = box()
 
     @Test fun assignment() = box()
+
+    @Test fun skipsGlobalDeclarations() = box()
 }