fix for default path renderer draws harlines without bloating

src/gpu/batches/GrDefaultPathRenderer.cpp

Index: src/gpu/batches/GrDefaultPathRenderer.cpp
diff --git a/src/gpu/batches/GrDefaultPathRenderer.cpp b/src/gpu/batches/GrDefaultPathRenderer.cpp
index 67bccb63b47346382bdd24487bd9f4ff99e98ac0..d0777e253fa70332ee36988fe5c0685a2506acd7 100644
--- a/src/gpu/batches/GrDefaultPathRenderer.cpp
+++ b/src/gpu/batches/GrDefaultPathRenderer.cpp
@@ -386,6 +386,12 @@ private:
         fGeoData.push_back(geometry);
 
         this->setBounds(devBounds);
+
+        // This is b.c. hairlines are notionally infinitely thin so without expansion
+        // two overlapping lines could be reordered even though they hit the same pixels.
+        if (isHairline) {
+            fBounds.outset(0.5f, 0.5f);
+        }
     }
 
     bool onCombineIfPossible(GrBatch* t, const GrCaps& caps) override {