Add test on bytecode text

Test data should be a Kotlin source file with zero or more comments e.g. of
the form: '// 1 INVOKEVIRTUAL'. The test then checks that the generated
bytecode for this file contains exactly one occurrence of the string
'INVOKEVIRTUAL'

compiler/testData/codegen/bytecodeText/statements/ifSingleBranch.kt

@@ -0,0 +1,11 @@
+fun foo() {
+    if (0 < 1) {
+        return
+    }
+    
+    if (1 < 2) else {
+        return
+    }
+}
+
+// 0 GETSTATIC

compiler/testData/codegen/bytecodeText/statements/ifThenElse.kt

@@ -0,0 +1,11 @@
+fun z(b: Boolean) {}
+
+fun foo(b: Boolean) {
+    if (b) {
+        z(b)
+    } else {
+        z(b)
+    }
+}
+
+// 0 GETSTATIC

compiler/testData/codegen/bytecodeText/statements/ifThenElseEmpty.kt

@@ -0,0 +1,7 @@
+fun foo(b: Boolean) {
+    if (b) {
+    } else {
+    }
+}
+
+// 0 GETSTATIC

compiler/testData/codegen/bytecodeText/statements/tryCatchFinally.kt

@@ -0,0 +1,25 @@
+fun z() {}
+
+fun foo() {
+    try {
+        z()
+    } catch (e: Exception) {
+        z()
+    }
+    
+    try {
+        z()
+    } finally {
+        z()
+    }
+
+    try {
+        z()
+    } catch (e: Exception) {
+        z()
+    } finally {
+        z()
+    }
+}
+
+// 0 GETSTATIC

compiler/testData/codegen/bytecodeText/statements/when.kt

@@ -0,0 +1,11 @@
+fun z() {}
+
+fun foo(x: Int) {
+    when {
+        x == 21 -> z()
+        x == 42 -> z()
+        else -> {}
+    }
+}
+
+// 0 GETSTATIC

compiler/testData/codegen/bytecodeText/statements/whenSubject.kt

@@ -0,0 +1,11 @@
+fun z() {}
+
+fun foo(x: Int) {
+    when (x) {
+        21 -> z()
+        42 -> z()
+        else -> {}
+    }
+}
+
+// 0 GETSTATIC