Remove variable shadowing in blink/svg

In an effort to reduce or even ban symbol shadowing, this renames
a variable to avoid such shadowing. I'm interested in prohibiting
shadowing because I think it might prevent potential jumbo problems.

The exact error this avoids is:
third_party/blink/renderer/core/svg/svg_svg_element.cc:456:28: error: declaration shadows a local variable [-Werror,-Wshadow]
      TransformationMatrix transform;
                           ^
third_party/blink/renderer/core/svg/svg_svg_element.cc:449:19: note: previous declaration is here
  AffineTransform transform;
                  ^

Bug: 923510
Change-Id: I99c001d0eb513d73bfc33d540601479a6fd7280d
Reviewed-on: https://chromium-review.googlesource.com/c/1482975
Auto-Submit: Daniel Bratell <bratell@opera.com>
Commit-Queue: Fredrik Söderquist <fs@opera.com>
Reviewed-by: Fredrik Söderquist <fs@opera.com>
Cr-Commit-Position: refs/heads/master@{#634676}

third_party/blink/renderer/core/svg/svg_svg_element.cc

@@ -453,24 +453,24 @@ AffineTransform SVGSVGElement::LocalCoordinateSpaceTransform(
                         y_->CurrentValue()->Value(length_context));
   } else if (mode == kScreenScope) {
     if (LayoutObject* layout_object = this->GetLayoutObject()) {
-      TransformationMatrix transform;
+      TransformationMatrix matrix;
       // Adjust for the zoom level factored into CSS coordinates (WK bug
       // #96361).
-      transform.Scale(1.0 / layout_object->StyleRef().EffectiveZoom());
+      matrix.Scale(1.0 / layout_object->StyleRef().EffectiveZoom());
 
       // Apply transforms from our ancestor coordinate space, including any
       // non-SVG ancestor transforms.
-      transform.Multiply(layout_object->LocalToAbsoluteTransform());
+      matrix.Multiply(layout_object->LocalToAbsoluteTransform());
 
       // At the SVG/HTML boundary (aka LayoutSVGRoot), we need to apply the
       // localToBorderBoxTransform to map an element from SVG viewport
       // coordinates to CSS box coordinates.
-      transform.Multiply(
+      matrix.Multiply(
           ToLayoutSVGRoot(layout_object)->LocalToBorderBoxTransform());
       // Drop any potential non-affine parts, because we're not able to convey
       // that information further anyway until getScreenCTM returns a DOMMatrix
       // (4x4 matrix.)
-      return transform.ToAffineTransform();
+      return matrix.ToAffineTransform();
     }
   }
   if (!HasEmptyViewBox()) {