message: Fix the bug where the terminal font size would reset after splitting/unsplitting
diff: @@ -597,6 +597,8 @@ export class EtTerminal extends ThemeableElementBase implements CommandPaletteRe
  // This was already attached at least once.
  this._scheduleResize();
  }
  +
  + this._setFontSizeInCss(this._fontSizeAdjustment);
  }
  /**
  @@ -1308,13 +1310,16 @@ export class EtTerminal extends ThemeableElementBase implements CommandPaletteRe
  const newAdjustment = Math.min(Math.max(this._fontSizeAdjustment + delta, MINIMUM_FONT_SIZE), MAXIMUM_FONT_SIZE);
  if (newAdjustment !== this._fontSizeAdjustment) {
  this._fontSizeAdjustment = newAdjustment;
  + this._setFontSizeInCss(newAdjustment);
  + }
  + }
  + private _setFontSizeInCss(size: number): void {
  const styleElement = <HTMLStyleElement> DomUtils.getShadowId(this, ID_CSS_VARS);
  - (<any>styleElement.sheet).cssRules[0].style.cssText = this._getCssFontSizeRule(newAdjustment); // Type stubs are missing cssRules.
  + (<any>styleElement.sheet).cssRules[0].style.cssText = this._getCssFontSizeRule(size); // Type stubs are missing cssRules.
  this._armResizeCanary = true;
  // Don't refresh. Let the Resize Canary detect the real change in the DOM when it arrives.
  }
  - }
  private _resetFontSize(): void {
  this._adjustFontSize(-this._fontSizeAdjustment);
  