[FCP++] Text: ignore text blocking on webfont

Currently FCP++ doesn't ignore the text paint in the block stage. The block
stage happens when we have font-display:block for a text node and the
webfont of the text is not yet loaded.

FCP++ should ignore the text because it's not visible to users. The text should
be captured only after the text starts to be visible.

The block stage is controlled by Font::ShouldSkipDrawing(). When a text node
is blocked on web-font, the text would be set to invisible-font. So FCP++ should
use this method to tell whether the text would not be drawn due to the
invisible font.

Bug: 944530
Change-Id: If80a5bdeccce0896d0e4e836c89bfd9aefbd627d
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1609669
Commit-Queue: Liquan (Max) Gu <maxlg@chromium.org>
Reviewed-by: Liquan (Max) Gu <maxlg@chromium.org>
Reviewed-by: Xianzhu Wang <wangxianzhu@chromium.org>
Cr-Commit-Position: refs/heads/master@{#659661}

third_party/blink/renderer/core/paint/ellipsis_box_painter.cc

@@ -72,7 +72,8 @@ void EllipsisBoxPainter::PaintEllipsis(const PaintInfo& paint_info,
   // TODO(npm): Check that there are non-whitespace characters. See
   // crbug.com/788444.
   context.GetPaintController().SetTextPainted();
-  if (RuntimeEnabledFeatures::FirstContentfulPaintPlusPlusEnabled()) {
+  if (RuntimeEnabledFeatures::FirstContentfulPaintPlusPlusEnabled() &&
+      !font.ShouldSkipDrawing()) {
     // We should consider using the text node as the tracking node, instead of
     // the line layout item.
     Node* node = ellipsis_box_.GetLineLayoutItem().GetNode();

third_party/blink/renderer/core/paint/file_upload_control_painter.cc

@@ -78,7 +78,8 @@ void FileUploadControlPainter::PaintObject(const PaintInfo& paint_info,
     paint_info.context.DrawBidiText(
         font, text_run_paint_info,
         FloatPoint(RoundToInt(text_x), RoundToInt(text_y)));
-    if (RuntimeEnabledFeatures::FirstContentfulPaintPlusPlusEnabled()) {
+    if (RuntimeEnabledFeatures::FirstContentfulPaintPlusPlusEnabled() &&
+        !font.ShouldSkipDrawing()) {
       PaintTimingDetector::NotifyTextPaint(
           layout_file_upload_control_, paint_info.context.GetPaintController()
                                            .CurrentPaintChunkProperties());

third_party/blink/renderer/core/paint/inline_text_box_painter.cc

@@ -430,7 +430,8 @@ void InlineTextBoxPainter::Paint(const PaintInfo& paint_info,
     context.ConcatCTM(TextPainterBase::Rotation(
         box_rect, TextPainterBase::kCounterclockwise));
   }
-  if (RuntimeEnabledFeatures::FirstContentfulPaintPlusPlusEnabled()) {
+  if (RuntimeEnabledFeatures::FirstContentfulPaintPlusPlusEnabled() &&
+      !font.ShouldSkipDrawing()) {
     PaintTimingDetector::NotifyTextPaint(
         InlineLayoutObject(),
         paint_info.context.GetPaintController().CurrentPaintChunkProperties());

third_party/blink/renderer/core/paint/ng/ng_text_painter.cc

@@ -64,7 +64,8 @@ void NGTextPainter::PaintInternalFragment(
     // TODO(npm): Check that there are non-whitespace characters. See
     // crbug.com/788444.
     graphics_context_.GetPaintController().SetTextPainted();
-    if (RuntimeEnabledFeatures::FirstContentfulPaintPlusPlusEnabled()) {
+    if (RuntimeEnabledFeatures::FirstContentfulPaintPlusPlusEnabled() &&
+        !font_.ShouldSkipDrawing()) {
       PaintTimingDetector::NotifyTextPaint(
           *fragment_.GetLayoutObject(),
           graphics_context_.GetPaintController().CurrentPaintChunkProperties());

third_party/blink/renderer/core/paint/svg_inline_text_box_painter.cc

@@ -470,7 +470,8 @@ void SVGInlineTextBoxPainter::PaintText(const PaintInfo& paint_info,
   // TODO(npm): Check that there are non-whitespace characters. See
   // crbug.com/788444.
   context.GetPaintController().SetTextPainted();
-  if (RuntimeEnabledFeatures::FirstContentfulPaintPlusPlusEnabled()) {
+  if (RuntimeEnabledFeatures::FirstContentfulPaintPlusPlusEnabled() &&
+      !scaled_font.ShouldSkipDrawing()) {
     PaintTimingDetector::NotifyTextPaint(
         InlineLayoutObject(),
         paint_info.context.GetPaintController().CurrentPaintChunkProperties());

third_party/blink/renderer/platform/fonts/font.h

@@ -238,11 +238,11 @@ class PLATFORM_EXPORT Font {
   bool LoadingCustomFonts() const;
   bool IsFallbackValid() const;
 
- private:
   bool ShouldSkipDrawing() const {
     return font_fallback_list_ && font_fallback_list_->ShouldSkipDrawing();
   }
 
+ private:
   FontDescription font_description_;
   mutable scoped_refptr<FontFallbackList> font_fallback_list_;
   mutable unsigned can_shape_word_by_word_ : 1;