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ios/web/web_state/js/crw_js_plugin_placeholder_manager.mm

Index: ios/web/web_state/js/crw_js_plugin_placeholder_manager.mm
diff --git a/ios/web/web_state/js/crw_js_plugin_placeholder_manager.mm b/ios/web/web_state/js/crw_js_plugin_placeholder_manager.mm
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index 0000000000000000000000000000000000000000..6378d87b55f375b7d480c20e9da5dff83ad242b2
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+++ b/ios/web/web_state/js/crw_js_plugin_placeholder_manager.mm
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+// Copyright 2013 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#import "ios/web/web_state/js/crw_js_plugin_placeholder_manager.h"
+
+#include "base/logging.h"
+#include "base/strings/sys_string_conversions.h"
+#include "ios/web/public/web_client.h"
+
+@implementation CRWJSPluginPlaceholderManager
+
+namespace {
+
+// Returns a string with \ and ' escaped, and wrapped in '.
+// This is used instead of GetQuotedJSONString because that will convert
+// UTF-16 to UTF-8, which can cause problems when injecting scripts depending
+// on the page encoding (see crbug.com/302741).
+NSString* EscapedQuotedString(NSString* string) {
+  string = [string stringByReplacingOccurrencesOfString:@"\\"
+                                             withString:@"\\\\"];
+  string = [string stringByReplacingOccurrencesOfString:@"'"
+                                             withString:@"\\'"];
+  return [NSString stringWithFormat:@"'%@'", string];
+}
+
+}
+
+#pragma mark -
+#pragma mark ProtectedMethods
+
+- (NSString*)scriptPath {
+  return @"plugin_placeholder";
+}
+
+- (NSString*)presenceBeacon {
+  return @"__gCrWeb.plugin";
+}
+
+- (NSString*)staticInjectionContent {
+  NSString* baseContent = [super staticInjectionContent];
+  DCHECK(web::GetWebClient());
+  NSString* pluginNotSupportedText = base::SysUTF16ToNSString(
+      web::GetWebClient()->GetPluginNotSupportedText());
+  NSString* placeholderCall = [NSString stringWithFormat:
+      @"__gCrWeb.plugin.addPluginPlaceholders(%@);",
+          EscapedQuotedString(pluginNotSupportedText)];
+  return [baseContent stringByAppendingString:placeholderCall];
+}
+
+@end