Make PEM debugging section fixed width in the SSL interstitial

components/security_interstitials/core/browser/resources/interstitial_v2.js

Index: components/security_interstitials/core/browser/resources/interstitial_v2.js
diff --git a/components/security_interstitials/core/browser/resources/interstitial_v2.js b/components/security_interstitials/core/browser/resources/interstitial_v2.js
index 332f6939fc340ff453158478974ec0693860c391..284687e510c01cce167ede5e23445d60a3573d49 100644
--- a/components/security_interstitials/core/browser/resources/interstitial_v2.js
+++ b/components/security_interstitials/core/browser/resources/interstitial_v2.js
@@ -68,8 +68,9 @@ function handleKeypress(e) {
  * (error-debugging-info) visible.
  * @param {string} title  The name of this debugging field.
  * @param {string} value  The value of the debugging field.
+ * @param {string=} extraCssClass Additional CSS classes. Optional.
  */
-function appendDebuggingField(title, value) {
+function appendDebuggingField(title, value, extraCssClass) {
   // The values input here are not trusted. Never use innerHTML on these
   // values!
   var spanTitle = document.createElement('span');
@@ -78,6 +79,9 @@ function appendDebuggingField(title, value) {
 
   var spanValue = document.createElement('span');
   spanValue.classList.add('debugging-value');
+  if (extraCssClass) {
+    spanValue.classList.add(extraCssClass);
+  }
   spanValue.innerText = value;
 
   var pElem = document.createElement('p');