Adds constant for the Upgrade-Insecure-Requests header.

https://w3c.github.io/webappsec-upgrade-insecure-requests/#preference

RELNOTES=Adds constant for the Upgrade-Insecure-Requests header.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=264984423

Author: jerryzz0

android/guava/src/com/google/common/net/HttpHeaders.java

@@ -171,7 +171,14 @@ private ReferrerPolicyValues() {}
   public static final String TE = "TE";
   /** The HTTP {@code Upgrade} header field name. */
   public static final String UPGRADE = "Upgrade";
-  /** The HTTP {@code User-Agent} header field name. */
+  /**
+   * The HTTP <a href="https://w3c.github.io/webappsec-upgrade-insecure-requests/#preference">{@code
+   * Upgrade-Insecure-Requests}</a> header field name.
+   *
+   * @since NEXT
+   */
+  public static final String UPGRADE_INSECURE_REQUESTS = "Upgrade-Insecure-Requests";
+
   public static final String USER_AGENT = "User-Agent";
 
   // HTTP Response header fields

guava/src/com/google/common/net/HttpHeaders.java

@@ -171,7 +171,14 @@ private ReferrerPolicyValues() {}
   public static final String TE = "TE";
   /** The HTTP {@code Upgrade} header field name. */
   public static final String UPGRADE = "Upgrade";
-  /** The HTTP {@code User-Agent} header field name. */
+  /**
+   * The HTTP <a href="https://w3c.github.io/webappsec-upgrade-insecure-requests/#preference">{@code
+   * Upgrade-Insecure-Requests}</a> header field name.
+   *
+   * @since NEXT
+   */
+  public static final String UPGRADE_INSECURE_REQUESTS = "Upgrade-Insecure-Requests";
+
   public static final String USER_AGENT = "User-Agent";
 
   // HTTP Response header fields