Fix SetAhemBody to set proper font size

LayoutTextTest and LayoutTextFragmentTest do not set font-size
when SetAhemBody is used. This caused DCHECK failures added in
CL:1111895 due to too much rounding errors.

This patch fixes that by setting the font-size to 10px.

Bug: 636993
Cq-Include-Trybots: luci.chromium.try:linux_layout_tests_layout_ng
Change-Id: I6e945a6f07902c50bbfcbca4014d324ba1ae1d0a
Reviewed-on: https://chromium-review.googlesource.com/1113697Reviewed-by: Xiaocheng Hu <xiaochengh@chromium.org>
Commit-Queue: Koji Ishii <kojii@chromium.org>
Cr-Commit-Position: refs/heads/master@{#570289}

third_party/blink/renderer/core/layout/layout_text_fragment_test.cc

@@ -26,7 +26,7 @@ class LayoutTextFragmentTest : public RenderingTest {
 
   void SetAhemBody(const char* message, const unsigned width) {
     SetBodyInnerHTML(String::Format(
-        "<div id='target' style='font: Ahem; width: %uem'>%s</div>", width,
+        "<div id='target' style='font: 10px Ahem; width: %uem'>%s</div>", width,
         message));
   }
 

third_party/blink/renderer/core/layout/layout_text_test.cc

@@ -27,7 +27,7 @@ class LayoutTextTest : public RenderingTest {
 
   void SetAhemBody(const char* message, const unsigned width) {
     SetBodyInnerHTML(String::Format(
-        "<div id='target' style='font: Ahem; width: %uem'>%s</div>", width,
+        "<div id='target' style='font: 10px Ahem; width: %uem'>%s</div>", width,
         message));
   }
 

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

@@ -4,7 +4,6 @@
 
 #include "third_party/blink/renderer/core/layout/ng/inline/ng_line_breaker.h"
 
-#include "build/build_config.h"
 #include "third_party/blink/renderer/core/layout/layout_list_marker.h"
 #include "third_party/blink/renderer/core/layout/ng/inline/ng_bidi_paragraph.h"
 #include "third_party/blink/renderer/core/layout/ng/inline/ng_inline_break_token.h"
@@ -304,10 +303,7 @@ void NGLineBreaker::UpdatePosition(const NGLineInfo& line_info) {
 void NGLineBreaker::ComputeLineLocation(NGLineInfo* line_info) const {
   LayoutUnit bfc_line_offset = line_.line_opportunity.line_left_offset;
   LayoutUnit available_width = line_.AvailableWidth();
-// TODO(kojii): IsBeforeAfterNonCollapsedLineWrapSpace fails only on Mac
-#if !defined(OS_MACOSX)
   DCHECK_EQ(line_.position, line_info->ComputeWidth());
-#endif
 
   // Negative margins can make the position negative, but the inline size is
   // always positive or 0.