Control flow graph for safe calls corrected #KT-10913 Fixed

Also #KT-10186 Fixed
Also #KT-5198 Fixed

compiler/testData/diagnostics/tests/controlFlowAnalysis/nonLocalReturnUnreachable.kt

@@ -0,0 +1,25 @@
+// See also KT-5198 / KT-10186
+
+inline fun doCall(f: () -> Unit) = f()
+
+fun test1(nonLocal: String): String {
+    val localResult = doCall {
+        return nonLocal  //unreachable
+    }
+    return "NON_LOCAL_FAILED $localResult"  //unreachable
+}
+
+fun doSomething() {}
+
+fun test2() {
+    fun f(x: Any?) = x
+    f(null?.let { return })
+
+    // false unreachable here
+    doSomething()
+}
+
+fun test3(x: Any?): Boolean =
+    x?.let { 
+        return true
+    } ?: false

compiler/testData/diagnostics/tests/controlFlowAnalysis/nonLocalReturnUnreachable.txt

@@ -0,0 +1,7 @@
+package
+
+public inline fun doCall(/*0*/ f: () -> kotlin.Unit): kotlin.Unit
+public fun doSomething(): kotlin.Unit
+public fun test1(/*0*/ nonLocal: kotlin.String): kotlin.String
+public fun test2(): kotlin.Unit
+public fun test3(/*0*/ x: kotlin.Any?): kotlin.Boolean

compiler/testData/diagnostics/tests/controlFlowAnalysis/throwInLambda.kt

@@ -0,0 +1,12 @@
+// See KT-10913 Bogus unreachable code warning
+
+fun fn() : String? = null
+fun foo(): String {
+    val x = fn()?.let { throw Exception() } ?: "unreachable?"
+    return x
+}
+fun bar(): String {
+    val x = fn() ?: return ""
+    <!UNREACHABLE_CODE!>val <!UNUSED_VARIABLE!>y<!> =<!> x<!UNNECESSARY_SAFE_CALL!>?.<!>let { throw Exception() } <!USELESS_ELVIS, UNREACHABLE_CODE!>?: "unreachable"<!>
+    <!UNREACHABLE_CODE!>return y<!>
+}

compiler/testData/diagnostics/tests/controlFlowAnalysis/throwInLambda.txt

@@ -0,0 +1,5 @@
+package
+
+public fun bar(): kotlin.String
+public fun fn(): kotlin.String?
+public fun foo(): kotlin.String