[DevTools] Add minimum size to WebInspector.View.

Source/devtools/front_end/heapProfiler.css

Index: Source/devtools/front_end/heapProfiler.css
diff --git a/Source/devtools/front_end/heapProfiler.css b/Source/devtools/front_end/heapProfiler.css
index c0e5b91913b69a3651d6e82b451a8df853b66844..6e1fb5618f95444e33fadcbb1a47f33f5de0b42e 100644
--- a/Source/devtools/front_end/heapProfiler.css
+++ b/Source/devtools/front_end/heapProfiler.css
@@ -146,13 +146,17 @@
     height: 80px;
 }
 
+.heap-snapshot-view .retaining-paths-view {
+    overflow: hidden;
+}
+
 .heap-snapshot-view .retainers-view-header {
     background-image: url(Images/statusbarResizerVertical.png);
     background-color: rgb(236, 236, 236);
     border-bottom: 1px solid rgb(179, 179, 179);
     background-repeat: no-repeat;
     background-position: right center, center;
-    height: 21px;
+    flex: 0 0 21px;
 }
 
 .heap-snapshot-view .retainers-view-header .title > span {