Migrate deprecations in core, compiler, idea, tests

Replacing deprecated Char.toInt() with Char.code and
Number.toChar() with Number.toInt().toChar(), where Number is not Int.

KT-23451

compiler/daemon/src/org/jetbrains/kotlin/daemon/KotlinCompileDaemon.kt

@@ -47,7 +47,7 @@ class LogStream(name: String) : OutputStream() {
     val lineBuf = StringBuilder()
 
     override fun write(byte: Int) {
-        if (byte.toChar() == '\n') flush()
+        if (byte == '\n'.code) flush()
         else lineBuf.append(byte.toChar())
     }