Transition to explicit constructors in LayoutUnit

third_party/WebKit/Source/core/layout/LayoutBlockFlow.h

Index: third_party/WebKit/Source/core/layout/LayoutBlockFlow.h
diff --git a/third_party/WebKit/Source/core/layout/LayoutBlockFlow.h b/third_party/WebKit/Source/core/layout/LayoutBlockFlow.h
index cc1dc25e817df631e96b0409d12769b80ca4dd61..354dd0e832b54c160388f96dcf3d27438f0721b6 100644
--- a/third_party/WebKit/Source/core/layout/LayoutBlockFlow.h
+++ b/third_party/WebKit/Source/core/layout/LayoutBlockFlow.h
@@ -99,24 +99,24 @@ public:
 
     void deleteLineBoxTree() final;
 
-    LayoutUnit availableLogicalWidthForLine(LayoutUnit position, IndentTextOrNot indentText, LayoutUnit logicalHeight = 0) const
+    LayoutUnit availableLogicalWidthForLine(LayoutUnit position, IndentTextOrNot indentText, LayoutUnit logicalHeight = LayoutUnit()) const
     {
-        return max<LayoutUnit>(0, logicalRightOffsetForLine(position, indentText, logicalHeight) - logicalLeftOffsetForLine(position, indentText, logicalHeight));
+        return max<LayoutUnit>(LayoutUnit(), logicalRightOffsetForLine(position, indentText, logicalHeight) - logicalLeftOffsetForLine(position, indentText, logicalHeight));
     }
-    LayoutUnit logicalRightOffsetForLine(LayoutUnit position, IndentTextOrNot indentText, LayoutUnit logicalHeight = 0) const
+    LayoutUnit logicalRightOffsetForLine(LayoutUnit position, IndentTextOrNot indentText, LayoutUnit logicalHeight = LayoutUnit()) const
     {
         return logicalRightOffsetForLine(position, logicalRightOffsetForContent(), indentText, logicalHeight);
     }
-    LayoutUnit logicalLeftOffsetForLine(LayoutUnit position, IndentTextOrNot indentText, LayoutUnit logicalHeight = 0) const
+    LayoutUnit logicalLeftOffsetForLine(LayoutUnit position, IndentTextOrNot indentText, LayoutUnit logicalHeight = LayoutUnit()) const
     {
         return logicalLeftOffsetForLine(position, logicalLeftOffsetForContent(), indentText, logicalHeight);
     }
-    LayoutUnit startOffsetForLine(LayoutUnit position, IndentTextOrNot indentText, LayoutUnit logicalHeight = 0) const
+    LayoutUnit startOffsetForLine(LayoutUnit position, IndentTextOrNot indentText, LayoutUnit logicalHeight = LayoutUnit()) const
     {
         return style()->isLeftToRightDirection() ? logicalLeftOffsetForLine(position, indentText, logicalHeight)
             : logicalWidth() - logicalRightOffsetForLine(position, indentText, logicalHeight);
     }
-    LayoutUnit endOffsetForLine(LayoutUnit position, IndentTextOrNot indentText, LayoutUnit logicalHeight = 0) const
+    LayoutUnit endOffsetForLine(LayoutUnit position, IndentTextOrNot indentText, LayoutUnit logicalHeight = LayoutUnit()) const
     {
         return !style()->isLeftToRightDirection() ? logicalLeftOffsetForLine(position, indentText, logicalHeight)
             : logicalWidth() - logicalRightOffsetForLine(position, indentText, logicalHeight);
@@ -467,19 +467,19 @@ public:
 
         static LayoutUnit positiveMarginBeforeDefault(const LayoutBlockFlow* block)
         {
-            return std::max<LayoutUnit>(block->marginBefore(), 0);
+            return std::max<LayoutUnit>(block->marginBefore(), LayoutUnit());

[eae, 2016/01/29 03:38:11]

No need for template specification if you specify the type for the second
argument.

std::max(block->marginBefore(), LayoutUnit());

Given how common this is we might be better off with a helper function here.

Something like ensurePositive or clampToZero. Could be a static function or a
method on LayoutUnit.

block->marginBefore().clampToZero();

[leviw_travelin_and_unemployed, 2016/01/29 03:47:27]

Makes sense.

         }
         static LayoutUnit negativeMarginBeforeDefault(const LayoutBlockFlow* block)
         {
-            return std::max<LayoutUnit>(-block->marginBefore(), 0);
+            return std::max<LayoutUnit>(-block->marginBefore(), LayoutUnit());
         }
         static LayoutUnit positiveMarginAfterDefault(const LayoutBlockFlow* block)
         {
-            return std::max<LayoutUnit>(block->marginAfter(), 0);
+            return std::max<LayoutUnit>(block->marginAfter(), LayoutUnit());
         }
         static LayoutUnit negativeMarginAfterDefault(const LayoutBlockFlow* block)
         {
-            return std::max<LayoutUnit>(-block->marginAfter(), 0);
+            return std::max<LayoutUnit>(-block->marginAfter(), LayoutUnit());
         }
 
         MarginValues m_margins;