Consider Zoom factor when getting bounding rect.

third_party/WebKit/Source/web/mac/WebSubstringUtil.mm

Index: third_party/WebKit/Source/web/mac/WebSubstringUtil.mm
diff --git a/third_party/WebKit/Source/web/mac/WebSubstringUtil.mm b/third_party/WebKit/Source/web/mac/WebSubstringUtil.mm
index 350e9cb072ff92136e107450e6ab66a12decc15d..ab00dbecdf277007340030e0528374a2f53111dd 100644
--- a/third_party/WebKit/Source/web/mac/WebSubstringUtil.mm
+++ b/third_party/WebKit/Source/web/mac/WebSubstringUtil.mm
@@ -113,7 +113,13 @@ WebPoint getBaselinePoint(FrameView* frameView, const EphemeralRange& range, NSA
 {
     // Compute bottom left corner and convert to AppKit coordinates.
     // TODO(yosin) We shold avoid to create |Range| object. See crbug.com/529985.
-    IntRect stringRect = enclosingIntRect(createRange(range)->boundingRect());
+    float scale = frameView->frame().pageZoomFactor() * frameView->frame().textZoomFactor();

[yosin_UTC9, 2016/01/26 03:44:17]

Which coordinate space do you want to get?
See http://www.chromium.org/developers/design-documents/blink-coordinate-spaces

We may want to use coodinate space conversion function |FrameView|.

[Shu Chen, 2016/01/26 13:06:43]

Done. Will the new change work?

+    FloatRect rect = createRange(range)->boundingRect();
+    rect.setX(rect.x() * scale);
+    rect.setY(rect.y() * scale);
+    rect.setWidth(rect.width() * scale);
+    rect.setHeight(rect.height() * scale);
+    IntRect stringRect = enclosingIntRect(rect);
     IntPoint stringPoint = stringRect.minXMaxYCorner();
     stringPoint.setY(frameView->height() - stringPoint.y());