Reland "[ChromeDriver] Remove unused shadow DOM object cache"

This is a reland of 4fe92e6c

Original change's description:
> [ChromeDriver] Remove unused shadow DOM object cache
>
> ChromeDriver uses object caches for use while calling JavaScript
> functions. The data structure was designed to allow a separate cache for
> each shadow DOM, but that feature was never used, and objects in shadow
> DOMs have always been stored in the main page cache. This CL removes
> unused code, and resolves differences between test expectancies and
> actual code behavior. It prepares for future changes to make the object
> cache standard compliant.
>
> Bug: chromedriver:1461
> Change-Id: I10fcd94a7fd2359cc43fe6bc7241d36647e9d744
> Reviewed-on: https://chromium-review.googlesource.com/c/1485011
> Commit-Queue: John Chen <johnchen@chromium.org>
> Reviewed-by: Caleb Rouleau <crouleau@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#635754}

Bug: chromedriver:1461 chromedriver:2794
Change-Id: Iedd6b7e43eb256d65bf71fec7e66454ceb0f776c
Reviewed-on: https://chromium-review.googlesource.com/c/1490855Reviewed-by: Caleb Rouleau <crouleau@chromium.org>
Commit-Queue: John Chen <johnchen@chromium.org>
Cr-Commit-Position: refs/heads/master@{#635876}

chrome/test/chromedriver/chrome/web_view_impl.cc

@@ -361,7 +361,7 @@ Status WebViewImpl::CallFunction(const std::string& frame,
   std::string w3c = w3c_compliant_ ? "true" : "false";
   // TODO(zachconrad): Second null should be array of shadow host ids.
   std::string expression = base::StringPrintf(
-      "(%s).apply(null, [null, %s, %s, %s])",
+      "(%s).apply(null, [%s, %s, %s])",
       kCallFunctionScript,
       function.c_str(),
       json.c_str(),
@@ -1141,7 +1141,7 @@ Status GetNodeIdFromFunction(DevToolsClient* client,
   std::string w3c = w3c_compliant ? "true" : "false";
   // TODO(zachconrad): Second null should be array of shadow host ids.
   std::string expression = base::StringPrintf(
-      "(%s).apply(null, [null, %s, %s, %s, true])",
+      "(%s).apply(null, [%s, %s, %s, true])",
       kCallFunctionScript,
       function.c_str(),
       json.c_str(),

chrome/test/chromedriver/js/call_function.js

@@ -232,6 +232,7 @@ function getNodeRootThroughAnyShadows(node) {
 function getPageCache(opt_doc, opt_w3c) {
   var doc = opt_doc || document;
   var w3c = opt_w3c || false;
+  // |key| is a long random string, unlikely to conflict with anything else.
   var key = '$cdc_asdjflasutopfhvcZLmcfl_';
   if (w3c) {
     if (!(key in doc))
@@ -323,8 +324,6 @@ function unwrap(value, cache) {
  * between cached object reference IDs and actual JS objects. The cache will
  * automatically be pruned each call to remove stale references.
  *
- * @param  {Array<string>} shadowHostIds The host ids of the nested shadow
- *     DOMs the function should be executed in the context of.
  * @param {function(...[*]) : *} func The function to invoke.
  * @param {!Array<*>} args The array of arguments to supply to the function,
  *     which will be unwrapped before invoking the function.
@@ -336,7 +335,7 @@ function unwrap(value, cache) {
  *     unwrapped return was specified, this will be the function's pure return
  *     value.
  */
-function callFunction(shadowHostIds, func, args, w3c, opt_unwrappedReturn) {
+function callFunction(func, args, w3c, opt_unwrappedReturn) {
   if (w3c) {
     w3cEnabled = true;
     ELEMENT_KEY = 'element-6066-11e4-a52e-4f735466cecf';
@@ -344,15 +343,6 @@ function callFunction(shadowHostIds, func, args, w3c, opt_unwrappedReturn) {
   }
   var cache = getPageCache(null, w3cEnabled);
   cache.clearStale();
-  if (shadowHostIds && SHADOW_DOM_ENABLED) {
-    for (var i = 0; i < shadowHostIds.length; i++) {
-      var host = cache.retrieveItem(shadowHostIds[i]);
-      // TODO(zachconrad): Use the olderShadowRoot API when available to check
-      // all of the shadow roots.
-      cache = getPageCache(host.webkitShadowRoot, w3cEnabled);
-      cache.clearStale();
-    }
-  }
 
   if (opt_unwrappedReturn)
     return func.apply(null, unwrap(args, cache));

chrome/test/chromedriver/js/call_function_test.html

@@ -33,7 +33,7 @@ function testUUID() {
 function testCallFunctionNoArgs() {
   clearCache();
 
-  var result = callFunction(null, function() { return 1; }, []);
+  var result = callFunction(function() { return 1; }, []);
   assertEquals(0, result.status);
   assertEquals(1, result.value);
 }
@@ -41,12 +41,12 @@ function testCallFunctionNoArgs() {
 function testCallFunctionThrows() {
   clearCache();
 
-  var result = callFunction(null, function() { throw new Error('fake error'); },
+  var result = callFunction(function() { throw new Error('fake error'); },
       []);
   assertEquals(StatusCode.JAVA_SCRIPT_ERROR, result.status);
   assertEquals('fake error', result.value);
 
-  result = callFunction(null, function() {
+  result = callFunction(function() {
     var e = new Error('fake error');
     e.code = 77;
     e.message = 'CUSTOM';
@@ -62,7 +62,7 @@ function testCallFunctionArgs() {
   function func(primitive, elem) {
     return [primitive, elem.querySelector('div')];
   }
-  var result = callFunction(null, func, [1, wrap(document)]);
+  var result = callFunction(func, [1, wrap(document)]);
   assertEquals(0, result.status);
   assertEquals(1, result.value[0]);
   var cache = getPageCache();
@@ -75,7 +75,7 @@ function testCallFunctionArgsUnwrappedReturn() {
   function func(elem) {
     return elem.querySelector('div');
   }
-  var result = callFunction(null, func, [wrap(document)], false, true);
+  var result = callFunction(func, [wrap(document)], false, true);
   assertEquals(document.querySelector('div'), result);
 }
 
@@ -195,7 +195,7 @@ function testCallFunctionWithShadowHost() {
   }
   var wrappedHost = wrap(host);
   
-  var result = callFunction(null, func, [wrappedHost]);
+  var result = callFunction(func, [wrappedHost]);
   assertEquals(0, result.status);
   assertEquals(wrappedHost['ELEMENT'], result.value['ELEMENT']);
   var cache = getPageCache();
@@ -204,7 +204,7 @@ function testCallFunctionWithShadowHost() {
   document.body.removeChild(host);
 }
 
-function DISABLED_testCallFunctionWithShadowRoot() {
+function testCallFunctionWithShadowRoot() {
   clearCache();
 
   // Set up something in the shadow DOM.
@@ -218,20 +218,17 @@ function DISABLED_testCallFunctionWithShadowRoot() {
   var wrappedHost = wrap(host);
   var wrappedRoot = wrap(root);
   
-  // Trying without setting the shadow_path should fail.
-  var result = callFunction(null, func, [wrappedRoot]);
-  assertEquals(StatusCode.STALE_ELEMENT_REFERENCE, result.status);
-  // Should succeed with the shadow_path.
-  result = callFunction([wrappedHost['ELEMENT']], func, [wrappedRoot]);
+  // Should handle shadow root as an argument.
+  result = callFunction(func, [wrappedRoot]);
   assertEquals(0, result.status);
   assertEquals(wrappedRoot['ELEMENT'], result.value['ELEMENT']);
-  var cache = getPageCache(root);
+  var cache = getPageCache();
   assertEquals(root, unwrap(result.value, cache));
   
   document.body.removeChild(host);
 }
 
-function DISABLED_testCacheWithShadowDomAttached() {
+function testCacheWithShadowDomAttached() {
   clearCache();
   var pageCache = getPageCache();
   
@@ -242,17 +239,8 @@ function DISABLED_testCacheWithShadowDomAttached() {
   
   // Test with attached element in shadow DOM.
   var wrappedDiv = wrap(shadowDiv);
-  // It should NOT be in the page cache.
-  try {
-    unwrap(wrappedDiv, pageCache);
-    assert(false);
-  } catch (e) {
-    assertEquals(StatusCode.STALE_ELEMENT_REFERENCE, e.code);
-  }
-  // It should be in the shadow root cache.
-  var rootCache = getPageCache(root);
-  rootCache.clearStale();
-  var unwrappedDiv = unwrap(wrappedDiv, rootCache);
+  pageCache.clearStale();
+  var unwrappedDiv = unwrap(wrappedDiv, pageCache);
   assertEquals(shadowDiv, unwrappedDiv);
   
   document.body.removeChild(host);
@@ -269,7 +257,7 @@ function testCacheWithShadowDomDetachedChild() {
   // Test with detached element in shadow DOM.
   var wrappedDiv = wrap(shadowDiv);
   root.removeChild(shadowDiv);
-  var rootCache = getPageCache(root);
+  var rootCache = getPageCache();
   rootCache.clearStale();
   try {
     unwrap(wrappedDiv, rootCache);