Use comparison against nullptr when using Member in boolean contexts

This allows moving to explicit operator T* for Member and also speeds up
the methods as boolean checks can work on compressed Member without
requiring decompression. See here [1] for the operator== overload.

This was automatically converted using
```
autoninja -C out/Release blink_tests -k 0  \
| grep " error: no viable conversion from returned value of type" \
| sort \
| uniq -c \
| sort -nr
| grep "'bool'" > out-bool.log
```

The build errors lead to a simple replace:
```
import fileinput
import re
import sys

bool_regex = r'(.*return\s)(.*)(;.*)$'
bool_replace = r'\1 \2 != nullptr \3'

def replace(file_name, line_nr):
  i = 1
  for line in fileinput.input(file_name, inplace=1):
    if i == line_nr:
      line = re.sub(bool_regex, bool_replace, line)
    sys.stdout.write(line)
    i += 1

with open (sys.argv[1]) as log_file:
  for line in log_file:
    file_parts = line.lstrip().split(' ')[1].split(':')
    file_name, line_nr = file_parts[0], int(file_parts[1])
    replace(file_name, line_nr)
```

This approach is conservative and may leave behind some more
complicated uses which will be fixed manually later.

[1] https://source.chromium.org/chromium/chromium/src/+/main:v8/include/cppgc/member.h;l=454&ss%3Dchromium

Bug: chromium:1492410
Change-Id: If78d43b6ef99b810844fb78f71d9c3b73a36b34c
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/4942151
Reviewed-by: Steinar H Gunderson <sesse@chromium.org>
Reviewed-by: Kentaro Hara <haraken@chromium.org>
Commit-Queue: Michael Lippautz <mlippautz@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1210150}

third_party/blink/renderer/bindings/core/v8/async_iterable.h

@@ -45,7 +45,9 @@ class CORE_EXPORT AsyncIterationSourceBase
   // [1] https://webidl.spec.whatwg.org/#dfn-get-the-next-iteration-result
   virtual void GetNextIterationResult() = 0;
 
-  bool HasPendingPromise() const { return pending_promise_resolver_; }
+  bool HasPendingPromise() const {
+    return pending_promise_resolver_ != nullptr;
+  }
 
   // Returns the pending promise resolver by removing it from this instance.
   ScriptPromiseResolver* TakePendingPromiseResolver() {

third_party/blink/renderer/bindings/core/v8/js_event_handler.h

@@ -86,7 +86,7 @@ class CORE_EXPORT JSEventHandler : public JSBasedEventListener {
   void SetCompiledHandler(ScriptState* incumbent_script_state,
                           v8::Local<v8::Function> listener);
 
-  bool HasCompiledHandler() const { return event_handler_; }
+  bool HasCompiledHandler() const { return event_handler_ != nullptr; }
 
   // For checking special types of EventHandler.
   bool IsOnErrorEventHandler() const {

third_party/blink/renderer/core/animation/string_keyframe.h

@@ -213,7 +213,7 @@ class CORE_EXPORT StringKeyframe : public Keyframe {
     // Two shorthands with overlapping longhand properties are sorted based
     // on the number of longhand properties in their expansions.
     bool IsLogical() { return is_logical_; }
-    bool IsShorthand() { return css_property_value_set_; }
+    bool IsShorthand() { return css_property_value_set_ != nullptr; }
     unsigned ExpansionCount() {
       return css_property_value_set_ ? css_property_value_set_->PropertyCount()
                                      : 1;

third_party/blink/renderer/core/css/font_face.h

@@ -154,7 +154,7 @@ class CORE_EXPORT FontFace : public ScriptWrappable,
   }
   FontMetricsOverride GetFontMetricsOverride() const;
 
-  bool HasSizeAdjust() const { return size_adjust_; }
+  bool HasSizeAdjust() const { return size_adjust_ != nullptr; }
   float GetSizeAdjust() const;
 
   Document* GetDocument() const;

third_party/blink/renderer/core/css/parser/css_parser_context.h

@@ -132,7 +132,7 @@ class CORE_EXPORT CSSParserContext final
   void Count(WebFeature) const;
   void Count(CSSParserMode, CSSPropertyID) const;
   void CountDeprecation(WebFeature) const;
-  bool IsUseCounterRecordingEnabled() const { return document_; }
+  bool IsUseCounterRecordingEnabled() const { return document_ != nullptr; }
   bool IsDocumentHandleEqual(const Document* other) const;
   const Document* GetDocument() const;
   const ExecutionContext* GetExecutionContext() const;

third_party/blink/renderer/core/css/style_scope.h

@@ -60,7 +60,7 @@ class CORE_EXPORT StyleScope final : public GarbageCollected<StyleScope> {
   StyleRule* RuleForNesting() const { return from_; }
 
   // https://drafts.csswg.org/css-cascade-6/#implicit-scope
-  bool IsImplicit() const { return contents_; }
+  bool IsImplicit() const { return contents_ != nullptr; }
 
   // True if this StyleScope has an implicit root at the specified element.
   // This is used to find the roots for prelude-less @scope rules.

third_party/blink/renderer/core/display_lock/display_lock_context.h

@@ -241,7 +241,7 @@ class CORE_EXPORT DisplayLockContext final
     is_details_slot_ = is_details_slot;
   }
 
-  bool HasElement() const { return element_; }
+  bool HasElement() const { return element_ != nullptr; }
 
   // Top layer implementation.
   void NotifyHasTopLayerElement();

third_party/blink/renderer/core/html/lazy_load_frame_observer.h

@@ -38,7 +38,9 @@ class LazyLoadFrameObserver final
   ~LazyLoadFrameObserver();
 
   void DeferLoadUntilNearViewport(const ResourceRequestHead&, WebFrameLoadType);
-  bool IsLazyLoadPending() const { return lazy_load_intersection_observer_; }
+  bool IsLazyLoadPending() const {
+    return lazy_load_intersection_observer_ != nullptr;
+  }
   void CancelPendingLazyLoad();
 
   void LoadImmediately();

third_party/blink/renderer/core/html/portal/portal_contents.h

@@ -49,7 +49,7 @@ class PortalContents : public GarbageCollected<PortalContents>,
   bool IsValid() const { return remote_portal_.is_bound(); }
 
   // Returns true if this contents is currently being activated.
-  bool IsActivating() const { return activation_delegate_; }
+  bool IsActivating() const { return activation_delegate_ != nullptr; }
 
   // Returns an unguessable token which uniquely identifies the contents, if
   // valid.

third_party/blink/renderer/core/layout/layout_image_resource.h

@@ -50,7 +50,7 @@ class CORE_EXPORT LayoutImageResource
 
   void SetImageResource(ImageResourceContent*);
   ImageResourceContent* CachedImage() const { return cached_image_.Get(); }
-  virtual bool HasImage() const { return cached_image_; }
+  virtual bool HasImage() const { return cached_image_ != nullptr; }
   ResourcePriority ComputeResourcePriority() const;
 
   void ResetAnimation();

third_party/blink/renderer/core/layout/list/unpositioned_list_marker.h

@@ -56,7 +56,7 @@ class CORE_EXPORT UnpositionedListMarker final {
   explicit UnpositionedListMarker(LayoutOutsideListMarker*);
   explicit UnpositionedListMarker(const NGBlockNode&);
 
-  explicit operator bool() const { return marker_layout_object_; }
+  explicit operator bool() const { return marker_layout_object_ != nullptr; }
 
   // Returns the baseline that the list-marker should place itself along.
   //

third_party/blink/renderer/core/layout/ng/exclusions/ng_layout_opportunity.h

@@ -43,7 +43,7 @@ struct CORE_EXPORT NGLayoutOpportunity final {
 
   // Returns if the opportunity has any shapes which may affect a line layout
   // opportunity.
-  bool HasShapeExclusions() const { return shape_exclusions; }
+  bool HasShapeExclusions() const { return shape_exclusions != nullptr; }
 
   // Returns if the given delta (relative to the start of the opportunity) will
   // be below any shapes.

third_party/blink/renderer/core/layout/scroll_anchor.h

@@ -56,7 +56,7 @@ class CORE_EXPORT ScrollAnchor final {
   void SetScroller(ScrollableArea*);
 
   // Returns true if the underlying scroller is set.
-  bool HasScroller() const { return scroller_; }
+  bool HasScroller() const { return scroller_ != nullptr; }
 
   // The LayoutObject we are currently anchored to. Lazily computed during
   // notifyBeforeLayout() and cached until the next call to clear().

third_party/blink/renderer/core/loader/document_loader.h

@@ -196,7 +196,9 @@ class CORE_EXPORT DocumentLoader : public GarbageCollected<DocumentLoader>,
   // same number of time than BlockParser().
   void BlockParser() override;
   void ResumeParser() override;
-  bool HasBeenLoadedAsWebArchive() const override { return archive_; }
+  bool HasBeenLoadedAsWebArchive() const override {
+    return archive_ != nullptr;
+  }
   WebArchiveInfo GetArchiveInfo() const override;
   bool LastNavigationHadTransientUserActivation() const override {
     return last_navigation_had_transient_user_activation_;

third_party/blink/renderer/core/script/pending_script.h

@@ -140,7 +140,7 @@ class CORE_EXPORT PendingScript : public GarbageCollected<PendingScript>,
     return false;
   }
 
-  bool IsWatchingForLoad() const { return client_; }
+  bool IsWatchingForLoad() const { return client_ != nullptr; }
 
  protected:
   PendingScript(ScriptElementBase*,

third_party/blink/renderer/core/script/xml_parser_script_runner.h

@@ -26,7 +26,9 @@ class XMLParserScriptRunner final
   XMLParserScriptRunner& operator=(const XMLParserScriptRunner&) = delete;
   ~XMLParserScriptRunner() override;
 
-  bool HasParserBlockingScript() const { return parser_blocking_script_; }
+  bool HasParserBlockingScript() const {
+    return parser_blocking_script_ != nullptr;
+  }
 
   void ProcessScriptElement(Document&, Element*, TextPosition);
   void Detach();

third_party/blink/renderer/core/streams/readable_stream.h

@@ -220,7 +220,9 @@ class CORE_EXPORT ReadableStream : public ScriptWrappable {
   }
 
   // https://streams.spec.whatwg.org/#is-readable-stream-locked
-  static bool IsLocked(const ReadableStream* stream) { return stream->reader_; }
+  static bool IsLocked(const ReadableStream* stream) {
+    return stream->reader_ != nullptr;
+  }
 
   // https://streams.spec.whatwg.org/#readable-stream-pipe-to
   static ScriptPromise PipeTo(ScriptState*,

third_party/blink/renderer/core/streams/writable_stream.h

@@ -107,7 +107,9 @@ class CORE_EXPORT WritableStream : public ScriptWrappable {
 
   // Inherited methods used internally.
 
-  static bool IsLocked(const WritableStream* stream) { return stream->writer_; }
+  static bool IsLocked(const WritableStream* stream) {
+    return stream->writer_ != nullptr;
+  }
 
   void Serialize(ScriptState*, MessagePort*, ExceptionState&);
 

third_party/blink/renderer/modules/animationworklet/animator_definition.h

@@ -37,7 +37,7 @@ class MODULES_EXPORT AnimatorDefinition final
   V8AnimatorConstructor* ConstructorFunction() const { return constructor_; }
   V8AnimateCallback* AnimateFunction() const { return animate_; }
   V8StateCallback* StateFunction() const { return state_; }
-  bool IsStateful() const { return state_; }
+  bool IsStateful() const { return state_ != nullptr; }
 
  private:
   // This object keeps the constructor function, animate, and state function

third_party/blink/renderer/modules/serial/serial_port.h

@@ -67,7 +67,7 @@ class SerialPort final : public EventTarget,
   ScriptPromise ContinueClose(ScriptState*);
   void AbortClose();
   void StreamsClosed();
-  bool IsClosing() const { return close_resolver_; }
+  bool IsClosing() const { return close_resolver_ != nullptr; }
 
   void Flush(device::mojom::blink::SerialPortFlushMode mode,
              device::mojom::blink::SerialPort::FlushCallback callback);

third_party/blink/renderer/modules/webgl/webgl_context_object.h

@@ -46,7 +46,7 @@ class WebGLContextObject : public WebGLObject {
  protected:
   explicit WebGLContextObject(WebGLRenderingContextBase*);
 
-  bool HasGroupOrContext() const final { return context_; }
+  bool HasGroupOrContext() const final { return context_ != nullptr; }
 
   uint32_t CurrentNumberOfContextLosses() const final;
 

third_party/blink/renderer/modules/webgl/webgl_shared_object.h

@@ -56,7 +56,7 @@ class WebGLSharedObject : public WebGLObject {
  protected:
   explicit WebGLSharedObject(WebGLRenderingContextBase*);
 
-  bool HasGroupOrContext() const final { return context_group_; }
+  bool HasGroupOrContext() const final { return context_group_ != nullptr; }
 
   uint32_t CurrentNumberOfContextLosses() const final;