Remove stale platform-specific expectations

LayoutTests/platform/mac/media/video-volume-slider-expected.txt

Index: LayoutTests/platform/mac/media/video-volume-slider-expected.txt
diff --git a/LayoutTests/platform/mac/media/video-volume-slider-expected.txt b/LayoutTests/platform/mac/media/video-volume-slider-expected.txt
deleted file mode 100644
index c7daf8a57f3d328a84680a4bfe3c9bc4e69f9dc8..0000000000000000000000000000000000000000
--- a/LayoutTests/platform/mac/media/video-volume-slider-expected.txt
+++ /dev/null
@@ -1,48 +0,0 @@
-layer at (0,0) size 800x600
-  RenderView at (0,0) size 800x600
-layer at (0,0) size 800x600
-  RenderBlock {HTML} at (0,0) size 800x600
-    RenderBody {BODY} at (8,8) size 784x584
-      RenderText {#text} at (0,0) size 433x18
-        text run at (0,0) width 433: "Tests if the volume slider is rendererd properly. This test assumes the"
-      RenderBR {BR} at (433,14) size 0x0
-      RenderText {#text} at (0,18) size 446x18
-        text run at (0,18) width 446: "volume slider is implmented and mouse over the right bottom corner of"
-      RenderBR {BR} at (446,32) size 0x0
-      RenderText {#text} at (0,36) size 270x18
-        text run at (0,36) width 270: "video element will show the volume slider."
-      RenderBR {BR} at (270,50) size 0x0
-      RenderText {#text} at (0,0) size 0x0
-layer at (8,62) size 320x240
-  RenderVideo {VIDEO} at (0,54) size 320x240
-layer at (8,62) size 320x240
-  RenderDeprecatedFlexibleBox (relative positioned) {DIV} at (0,0) size 320x240
-layer at (8,270) size 320x32
-  RenderDeprecatedFlexibleBox (relative positioned) {DIV} at (0,208) size 320x32 [bgcolor=#00000099]
-    RenderBlock {DIV} at (286,0) size 34x32
-layer at (15,276) size 18x19
-  RenderButton {INPUT} at (7,6) size 18x19
-layer at (38,270) size 256x32
-  RenderDeprecatedFlexibleBox (positioned) {DIV} at (30,0) size 256x32 [border: (1px solid #FFFFFF33) none (1px solid #FFFFFF33)]
-    RenderSlider {INPUT} at (7,7) size 184x18 [color=#328CDF] [bgcolor=#FFFFFF14] [border: (1px solid #FFFFFF33)]
-      RenderDeprecatedFlexibleBox {DIV} at (1,1) size 182x16
-        RenderBlock {DIV} at (0,0) size 173x29
-        RenderBlock {DIV} at (173,0) size 9x29
-layer at (235,276) size 58x20 scrollHeight 21
-  RenderDeprecatedFlexibleBox {DIV} at (197,6) size 58x20 [color=#FFFFFF]
-    RenderBlock (anonymous) at (8,0) size 42x21
-      RenderText {#text} at (0,2) size 41x17
-        text run at (0,2) width 41: "00:00"
-layer at (46,272) size 9x30
-  RenderBlock (relative positioned) {DIV} at (0,-7) size 9x30
-layer at (294,170) size 34x100
-  RenderBlock (positioned) {DIV} at (286,-100) size 34x100 [bgcolor=#00000099]
-layer at (306,180) size 10x80
-  RenderSlider {INPUT} at (12,10) size 10x80
-    RenderDeprecatedFlexibleBox {DIV} at (0,0) size 10x80
-      RenderBlock {DIV} at (0,0) size 14x73
-      RenderBlock {DIV} at (0,73) size 14x7
-layer at (306,202) size 14x7
-  RenderBlock (relative positioned) {DIV} at (0,0) size 14x7
-layer at (294,270) size 34x32
-  RenderButton {INPUT} at (0,0) size 34x32