rustdoc: change mobile breakpoint to match CSS

Since it's possible to have a 700.5px viewport width, the JS needs to not
switch to mobile mode in such a setup.

Author: notriddle

src/librustdoc/html/static/js/main.js

@@ -737,7 +737,7 @@ function loadCss(cssFileName) {
 
     window.rustdocMobileScrollLock = function() {
         const mobile_topbar = document.querySelector(".mobile-topbar");
-        if (window.innerWidth < window.RUSTDOC_MOBILE_BREAKPOINT) {
+        if (window.innerWidth <= window.RUSTDOC_MOBILE_BREAKPOINT) {
             // This is to keep the scroll position on mobile.
             oldSidebarScrollPosition = window.scrollY;
             document.body.style.width = `${document.body.offsetWidth}px`;
@@ -783,7 +783,7 @@ function loadCss(cssFileName) {
     }
 
     window.addEventListener("resize", () => {
-        if (window.innerWidth >= window.RUSTDOC_MOBILE_BREAKPOINT &&
+        if (window.innerWidth > window.RUSTDOC_MOBILE_BREAKPOINT &&
             oldSidebarScrollPosition !== null) {
             // If the user opens the sidebar in "mobile" mode, and then grows the browser window,
             // we need to switch away from mobile mode and make the main content area scrollable.

src/librustdoc/html/static/js/storage.js

@@ -12,7 +12,7 @@ window.mainTheme = document.getElementById("mainThemeStyle");
 // WARNING: RUSTDOC_MOBILE_BREAKPOINT MEDIA QUERY
 // If you update this line, then you also need to update the media query with the same
 // warning in rustdoc.css
-window.RUSTDOC_MOBILE_BREAKPOINT = 701;
+window.RUSTDOC_MOBILE_BREAKPOINT = 700;
 
 const settingsDataset = (function() {
     const settingsElement = document.getElementById("default-settings");

src/test/rustdoc-gui/sidebar-mobile-scroll.goml

@@ -1,12 +1,12 @@
 // This test ensures that the mobile sidebar preserves scroll position.
 goto: "file://" + |DOC_PATH| + "/test_docs/struct.Foo.html"
 // Switching to "mobile view" by reducing the width to 600px.
-size: (600, 600)
+size: (700, 600)
 assert-css: (".sidebar", {"display": "block", "left": "-1000px"})
 
 // Scroll down.
 scroll-to: "//h2[@id='blanket-implementations']"
-assert-window-property: {"pageYOffset": "651"}
+assert-window-property: {"pageYOffset": "627"}
 
 // Open the sidebar menu.
 click: ".sidebar-menu-toggle"
@@ -21,11 +21,11 @@ assert-window-property: {"pageYOffset": "0"}
 // Close the sidebar menu. Make sure the scroll position gets restored.
 click: ".sidebar-menu-toggle"
 wait-for-css: (".sidebar", {"left": "-1000px"})
-assert-window-property: {"pageYOffset": "651"}
+assert-window-property: {"pageYOffset": "627"}
 
 // Now test that scrollability returns when the browser window is just resized.
 click: ".sidebar-menu-toggle"
 wait-for-css: (".sidebar", {"left": "0px"})
 assert-window-property: {"pageYOffset": "0"}
 size: (900, 600)
-assert-window-property: {"pageYOffset": "651"}
+assert-window-property: {"pageYOffset": "627"}