Use srcset's resource pixel density to determine intrinsic size

LayoutTests/platform/linux/fast/hidpi/image-srcset-relative-svg-canvas-expected.txt

Index: LayoutTests/platform/linux/fast/hidpi/image-srcset-relative-svg-canvas-expected.txt
diff --git a/LayoutTests/platform/linux/fast/hidpi/image-srcset-relative-svg-canvas-expected.txt b/LayoutTests/platform/linux/fast/hidpi/image-srcset-relative-svg-canvas-expected.txt
new file mode 100644
index 0000000000000000000000000000000000000000..b8c4867ba9f2ba34cc9439549826136c89606022
--- /dev/null
+++ b/LayoutTests/platform/linux/fast/hidpi/image-srcset-relative-svg-canvas-expected.txt
@@ -0,0 +1,36 @@
+layer at (0,0) size 800x600
+  RenderView at (0,0) size 800x600
+layer at (0,0) size 800x269
+  RenderBlock {HTML} at (0,0) size 800x269.03
+    RenderBody {BODY} at (8,19.91) size 784x233.13
+      RenderBlock {H2} at (0,0) size 784x27
+        RenderInline {A} at (0,0) size 59x26 [color=#0000EE]
+          RenderText {#text} at (0,0) size 59x26
+            text run at (0,0) width 59: "srcset"
+        RenderText {#text} at (59,0) size 184x26
+          text run at (59,0) width 184: " testcases for SVG"
+      RenderBlock {DIV} at (0,46.91) size 784x186.22 [border: (1px solid #808080)]
+        RenderBlock {H3} at (17,35.72) size 750x23
+          RenderText {#text} at (0,0) size 404x22
+            text run at (0,0) width 404: "Canvas relative SVG with explicit dimensions - 1x"
+        RenderBlock (floating) {DIV} at (650.22,77.44) size 116.78x91.78 [bgcolor=#EEEEEE] [border: (1px solid #CCCCCC)]
+          RenderText {#text} at (7,7) size 55x19
+            text run at (7,7) width 55: "expected"
+          RenderBR {BR} at (62,7) size 0x19
+          RenderImage {IMG} at (7,27.39) size 102x52 [border: (1px solid #000000)]
+          RenderText {#text} at (0,0) size 0x0
+        RenderBlock (floating) {DIV} at (517.44,77.44) size 116.78x91.78 [bgcolor=#EEEEEE] [border: (1px solid #CCCCCC)]
+          RenderText {#text} at (7,7) size 35x19
+            text run at (7,7) width 35: "actual"
+          RenderBR {BR} at (42,7) size 0x19
+          RenderImage {IMG} at (7,27.39) size 102x52 [border: (1px solid #000000)]
+          RenderText {#text} at (0,0) size 0x0
+        RenderBlock (anonymous) at (17,77.44) size 750x91.78
+          RenderText {#text} at (0,0) size 447x39
+            text run at (0,0) width 447: "This test should show an SVG image drawn into a canvas. The canvas and"
+            text run at (0,20) width 340: "image should look the same and both should be 100x50."
+          RenderBR {BR} at (340,20) size 0x19
+          RenderBlock {CODE} at (0,55) size 0x0
+          RenderText {#text} at (0,40) size 4x19
+            text run at (0,40) width 4: " "
+          RenderBR {BR} at (4,40) size 0x19