Avoid to check equality of saturated line width in MaxSizeFromMinSize::ComputeFromMinSize()

This patch changes |MaxSizeFromMinSize::ComputeFromMinSize()| to avoid
checking equality when line width calculation is saturated.

Note: This CL is similar to the CL[1] which dose same thing in
|NGLineBreaker|.

[1] http://crrev.com/c/Make NGLineBreaker::ComputeLineLocation() to avoid
DCHECK() when line width calculation saturated


Bug: 1112560
Change-Id: I1e1cc1135412cebfc2e2c3cf635dc08fe19578a6
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2340843
Auto-Submit: Yoshifumi Inoue <yosin@chromium.org>
Commit-Queue: Koji Ishii <kojii@chromium.org>
Reviewed-by: Koji Ishii <kojii@chromium.org>
Cr-Commit-Position: refs/heads/master@{#795418}

third_party/blink/renderer/core/layout/ng/inline/ng_inline_node.cc

@@ -1581,10 +1581,15 @@ static LayoutUnit ComputeContentSize(
       break;
 
     LayoutUnit inline_size = line_info.Width();
+#if DCHECK_IS_ON()
     // Text measurement is done using floats which may introduce small rounding
     // errors for near-saturated values.
-    DCHECK_EQ(inline_size.Round(),
-              line_info.ComputeWidth().ClampNegativeToZero().Round());
+    // See http://crbug.com/1112560
+    if (!LayoutUnit(line_info.ComputeWidthInFloat()).MightBeSaturated()) {
+      DCHECK_EQ(inline_size.Round(),
+                line_info.ComputeWidth().ClampNegativeToZero().Round());
+    }
+#endif
 
     for (const NGInlineItemResult& item_result : line_info.Results()) {
       DCHECK(item_result.item);

third_party/blink/renderer/core/layout/ng/inline/ng_inline_node_test.cc

@@ -475,6 +475,29 @@ TEST_F(NGInlineNodeTest, MinMaxSizesFloatsClearance) {
   EXPECT_EQ(160, sizes.max_size);
 }
 
+// For http://crbug.com/1112560
+TEST_F(NGInlineNodeTest, MinMaxSizesSaturated) {
+  LoadAhem();
+  SetupHtml("t", R"HTML(
+    <style>
+    b {
+        display: inline-block;
+        border-inline-start: groove;
+        width:1e8px;
+    }
+    #t {
+        float: left;
+        font: 10px Ahem;
+    }
+    </style>
+    <div id=t><b></b> <img></div>)HTML");
+
+  NGInlineNodeForTest node = CreateInlineNode();
+  MinMaxSizes sizes = ComputeMinMaxSizes(node);
+  EXPECT_EQ(LayoutUnit(33554431), sizes.min_size.Round());
+  // Note: |sizes.max_size.Round()| isn't |LayoutUnit::Max()| on some platform.
+}
+
 TEST_F(NGInlineNodeTest, MinMaxSizesTabulationWithBreakWord) {
   LoadAhem();
   SetupHtml("t", R"HTML(