Reduce how often LayoutSVGShape::updateShapeFromElement is called

LayoutTests/TestExpectations

Index: LayoutTests/TestExpectations
diff --git a/LayoutTests/TestExpectations b/LayoutTests/TestExpectations
index 859343b4f609a36e52217d1d758c0def6231bbf6..49b6ade56b1006778024fd3f9ffccbd4cb974029 100644
--- a/LayoutTests/TestExpectations
+++ b/LayoutTests/TestExpectations
@@ -934,6 +934,33 @@ crbug.com/334269 [ SnowLeopard ] fast/text/whitespace/018.html [ NeedsManualReba
 
 crbug.com/334269 [ Mac ] virtual/antialiasedtext/fast/text/line-break-after-question-mark.html [ Pass Failure ]
 
+crbug.com/491422 svg/W3C-SVG-1.1/animate-elem-40-t.svg [ NeedsRebaseline ]
+crbug.com/491422 svg/W3C-SVG-1.1/animate-elem-41-t.svg [ NeedsRebaseline ]
+crbug.com/491422 svg/W3C-SVG-1.1/animate-elem-78-t.svg [ NeedsRebaseline ]
+crbug.com/491422 svg/W3C-SVG-1.1/animate-elem-82-t.svg [ NeedsRebaseline ]
+crbug.com/491422 svg/custom/js-update-container.svg [ NeedsRebaseline ]
+crbug.com/491422 svg/custom/js-update-style.svg [ NeedsRebaseline ]
+crbug.com/491422 svg/custom/marker-changes.svg [ NeedsRebaseline ]
+crbug.com/491422 svg/custom/marker-strokeWidth-changes.svg [ NeedsRebaseline ]
+crbug.com/491422 svg/custom/marker-viewBox-changes.svg [ NeedsRebaseline ]
+crbug.com/491422 svg/custom/repaint-stroke-width-changes.svg [ NeedsRebaseline ]
+crbug.com/491422 svg/zoom/page/zoom-svg-through-object-with-absolute-size-2.xhtml [ NeedsRebaseline ]
+crbug.com/491422 svg/zoom/page/zoom-svg-through-object-with-absolute-size.xhtml [ NeedsRebaseline ]
+crbug.com/491422 svg/zoom/page/zoom-svg-through-object-with-percentage-size.xhtml [ NeedsRebaseline ]
+crbug.com/491422 virtual/slimmingpaint/svg/W3C-SVG-1.1/animate-elem-40-t.svg [ NeedsRebaseline ]
+crbug.com/491422 virtual/slimmingpaint/svg/W3C-SVG-1.1/animate-elem-41-t.svg [ NeedsRebaseline ]
+crbug.com/491422 virtual/slimmingpaint/svg/W3C-SVG-1.1/animate-elem-78-t.svg [ NeedsRebaseline ]
+crbug.com/491422 virtual/slimmingpaint/svg/W3C-SVG-1.1/animate-elem-82-t.svg [ NeedsRebaseline ]
+crbug.com/491422 virtual/slimmingpaint/svg/custom/js-update-container.svg [ NeedsRebaseline ]
+crbug.com/491422 virtual/slimmingpaint/svg/custom/js-update-style.svg [ NeedsRebaseline ]
+crbug.com/491422 virtual/slimmingpaint/svg/custom/marker-changes.svg [ NeedsRebaseline ]
+crbug.com/491422 virtual/slimmingpaint/svg/custom/marker-strokeWidth-changes.svg [ NeedsRebaseline ]
+crbug.com/491422 virtual/slimmingpaint/svg/custom/marker-viewBox-changes.svg [ NeedsRebaseline ]
+crbug.com/491422 virtual/slimmingpaint/svg/custom/repaint-stroke-width-changes.svg [ NeedsRebaseline ]
+crbug.com/491422 virtual/slimmingpaint/svg/zoom/page/zoom-svg-through-object-with-absolute-size-2.xhtml [ NeedsRebaseline ]
+crbug.com/491422 virtual/slimmingpaint/svg/zoom/page/zoom-svg-through-object-with-absolute-size.xhtml [ NeedsRebaseline ]
+crbug.com/491422 virtual/slimmingpaint/svg/zoom/page/zoom-svg-through-object-with-percentage-size.xhtml [ NeedsRebaseline ]
+
 crbug.com/339259 fast/flexbox/box-orient-button.html [ Pass Failure ]
 crbug.com/339394 [ Win Debug ] virtual/threaded/animations/animation-matrix-negative-scale-unmatrix.html [ Pass Failure ]
 crbug.com/339597 http/tests/navigation/back-to-redirect-with-frame.php [ Pass Timeout ]
@@ -1700,7 +1727,8 @@ crbug.com/485332 [ XP ] virtual/gpu/fast/canvas/canvas-as-image.html [ Failure ]
 # Temporary, until WebAXObjectProxy support lands.
 crbug.com/421771 accessibility/inline-text-box-next-on-line.html [ Skip ]
 
-crbug.com/486962 [ Linux Win Debug ] svg/W3C-SVG-1.1/animate-elem-41-t.svg [ ImageOnlyFailure ]
+# This should be uncommented when rebaselines are updated from crbug.com/491422.
+#crbug.com/486962 [ Linux Win Debug ] svg/W3C-SVG-1.1/animate-elem-41-t.svg [ ImageOnlyFailure ]
 crbug.com/486962 [ Linux Win Debug ] svg/W3C-SVG-1.1/animate-elem-46-t.svg [ ImageOnlyFailure ]
 
 crbug.com/321237 crbug.com/478014 [ SnowLeopard ] fast/text/international/complex-text-leading-space-wrapping.html [ ImageOnlyFailure ]