More useMemo inlining test cases

More test cases for useMemo inlining, including the problematic case we found 
internally and some similar tricky cases with labels.

compiler/forget/src/__tests__/fixtures/compiler/useMemo-inverted-if.expect.md

@@ -0,0 +1,37 @@
+
+## Input
+
+```javascript
+function Component(props) {
+  const x = useMemo(() => {
+    label: {
+      if (props.cond) {
+        break label;
+      }
+      return props.a;
+    }
+    return props.b;
+  });
+  return x;
+}
+
+```
+
+## Code
+
+```javascript
+function Component(props) {
+  let t17 = undefined;
+  bb10: {
+    if (props.cond) {
+      t17 = props.b;
+      break bb10;
+    }
+    t17 = props.a;
+  }
+  const x = t17;
+  return x;
+}
+
+```
+      

compiler/forget/src/__tests__/fixtures/compiler/useMemo-inverted-if.js

@@ -0,0 +1,12 @@
+function Component(props) {
+  const x = useMemo(() => {
+    label: {
+      if (props.cond) {
+        break label;
+      }
+      return props.a;
+    }
+    return props.b;
+  });
+  return x;
+}

compiler/forget/src/__tests__/fixtures/compiler/useMemo-nested-ifs.expect.md

@@ -0,0 +1,28 @@
+
+## Input
+
+```javascript
+function Component(props) {
+  const x = useMemo(() => {
+    if (props.cond) {
+      if (props.cond) {
+      }
+    }
+  }, [props.cond]);
+  return x;
+}
+
+```
+
+## Code
+
+```javascript
+function Component(props) {
+  if (props.cond) {
+    if (props.cond) {
+    }
+  }
+}
+
+```
+      

compiler/forget/src/__tests__/fixtures/compiler/useMemo-nested-ifs.js

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+function Component(props) {
+  const x = useMemo(() => {
+    if (props.cond) {
+      if (props.cond) {
+      }
+    }
+  }, [props.cond]);
+  return x;
+}

compiler/forget/src/__tests__/fixtures/compiler/useMemo-switch-return.expect.md

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+
+## Input
+
+```javascript
+function Component(props) {
+  const x = useMemo(() => {
+    let y;
+    switch (props.switch) {
+      case "foo": {
+        return "foo";
+      }
+      case "bar": {
+        y = "bar";
+        break;
+      }
+      default: {
+        y = props.y;
+      }
+    }
+    return y;
+  });
+  return x;
+}
+
+```
+
+## Code
+
+```javascript
+function Component(props) {
+  let t22 = undefined;
+  bb10: {
+    let y = undefined;
+    bb2: switch (props.switch) {
+      case "foo": {
+        t22 = "foo";
+        break bb10;
+      }
+      case "bar": {
+        y = "bar";
+        break bb2;
+      }
+      default: {
+        y = props.y;
+      }
+    }
+
+    t22 = y;
+  }
+  const x = t22;
+  return x;
+}
+
+```
+      

compiler/forget/src/__tests__/fixtures/compiler/useMemo-switch-return.js

@@ -0,0 +1,19 @@
+function Component(props) {
+  const x = useMemo(() => {
+    let y;
+    switch (props.switch) {
+      case "foo": {
+        return "foo";
+      }
+      case "bar": {
+        y = "bar";
+        break;
+      }
+      default: {
+        y = props.y;
+      }
+    }
+    return y;
+  });
+  return x;
+}