[LayoutNG] Fix ComputedStyle::ShouldUseTextIndent()

This patch fixes a typo that calls the default constructor instead of
the getter when the logic was copied from BreakingContextInlineHeaders.

This code path is used only in LayoutNG. Tests in fast/css3-text/css3-
text-indent/ still fail for other reasons when LayoutNG is enabled.

Bug: 636993, 346399
Change-Id: I9beea46bd11d3486bd9047ad98d14d960df8bad3
Reviewed-on: https://chromium-review.googlesource.com/670199
Commit-Queue: Koji Ishii <kojii@chromium.org>
Reviewed-by: Nico Weber <thakis@chromium.org>
Cr-Commit-Position: refs/heads/master@{#502501}
diff --git a/third_party/WebKit/Source/core/style/ComputedStyle.cpp b/third_party/WebKit/Source/core/style/ComputedStyle.cpp
index ebb63665..898d782 100644
--- a/third_party/WebKit/Source/core/style/ComputedStyle.cpp
+++ b/third_party/WebKit/Source/core/style/ComputedStyle.cpp
@@ -1256,7 +1256,8 @@
   bool should_use =
       is_first_line || (is_after_forced_break &&
                         GetTextIndentLine() != TextIndentLine::kFirstLine);
-  return TextIndentType() == TextIndentType::kNormal ? should_use : !should_use;
+  return GetTextIndentType() == TextIndentType::kNormal ? should_use
+                                                        : !should_use;
 }
 
 const AtomicString& ComputedStyle::TextEmphasisMarkString() const {