DevTools: Make sure network and main flamechart scales are in sync.

third_party/WebKit/Source/devtools/front_end/ui_lazy/flameChart.css

 .flame-chart-main-pane {
     overflow: hidden;
 }
 
 .flame-chart-marker-highlight-element {
     position: absolute;
     top: 0;
     height: 20px;
     width: 4px;
     margin: 0 -2px;
@@ skipping 20 matching lines @@
 .flame-chart-v-scroll {
     position: absolute;
     top: 0;
     right: 0;
     bottom: 0;
     overflow-x: hidden;
     z-index: 200;
     padding-left: 1px;
 }
 
+.flame-chart-v-scroll.always-show-scrollbar {
+    overflow-y: scroll;
+}
+
 :host-context(.platform-mac) .flame-chart-v-scroll {
     right: 2px;
     top: 3px;
     bottom: 3px;
 }
 
 /* force non-overlay scrollbars */
 :host-context(.platform-mac) ::-webkit-scrollbar {
     width: 8px;
 }
@@ skipping 50 matching lines @@
     white-space: nowrap;
 }
 
 .flame-chart-entry-info table tr td:first-child {
     font-weight: bold;
 }
 
 .flame-chart-entry-info table tr td span {
     margin-right: 5px;
 }