Replace existing autoloader with Composer-supplied

- Move Friendica namespace to `src`
- Move required `ezyang/htmlpurifier` to vendor
- Remove existing static autoloader
- Change boot.php reference to the autoloader

vendor/ezyang/htmlpurifier/library/HTMLPurifier/AttrDef.php

@@ -0,0 +1,138 @@
+<?php
+
+/**
+ * Base class for all validating attribute definitions.
+ *
+ * This family of classes forms the core for not only HTML attribute validation,
+ * but also any sort of string that needs to be validated or cleaned (which
+ * means CSS properties and composite definitions are defined here too).
+ * Besides defining (through code) what precisely makes the string valid,
+ * subclasses are also responsible for cleaning the code if possible.
+ */
+
+abstract class HTMLPurifier_AttrDef
+{
+
+    /**
+     * Tells us whether or not an HTML attribute is minimized.
+     * Has no meaning in other contexts.
+     * @type bool
+     */
+    public $minimized = false;
+
+    /**
+     * Tells us whether or not an HTML attribute is required.
+     * Has no meaning in other contexts
+     * @type bool
+     */
+    public $required = false;
+
+    /**
+     * Validates and cleans passed string according to a definition.
+     *
+     * @param string $string String to be validated and cleaned.
+     * @param HTMLPurifier_Config $config Mandatory HTMLPurifier_Config object.
+     * @param HTMLPurifier_Context $context Mandatory HTMLPurifier_Context object.
+     */
+    abstract public function validate($string, $config, $context);
+
+    /**
+     * Convenience method that parses a string as if it were CDATA.
+     *
+     * This method process a string in the manner specified at
+     * <http://www.w3.org/TR/html4/types.html#h-6.2> by removing
+     * leading and trailing whitespace, ignoring line feeds, and replacing
+     * carriage returns and tabs with spaces.  While most useful for HTML
+     * attributes specified as CDATA, it can also be applied to most CSS
+     * values.
+     *
+     * @note This method is not entirely standards compliant, as trim() removes
+     *       more types of whitespace than specified in the spec. In practice,
+     *       this is rarely a problem, as those extra characters usually have
+     *       already been removed by HTMLPurifier_Encoder.
+     *
+     * @warning This processing is inconsistent with XML's whitespace handling
+     *          as specified by section 3.3.3 and referenced XHTML 1.0 section
+     *          4.7.  However, note that we are NOT necessarily
+     *          parsing XML, thus, this behavior may still be correct. We
+     *          assume that newlines have been normalized.
+     */
+    public function parseCDATA($string)
+    {
+        $string = trim($string);
+        $string = str_replace(array("\n", "\t", "\r"), ' ', $string);
+        return $string;
+    }
+
+    /**
+     * Factory method for creating this class from a string.
+     * @param string $string String construction info
+     * @return HTMLPurifier_AttrDef Created AttrDef object corresponding to $string
+     */
+    public function make($string)
+    {
+        // default implementation, return a flyweight of this object.
+        // If $string has an effect on the returned object (i.e. you
+        // need to overload this method), it is best
+        // to clone or instantiate new copies. (Instantiation is safer.)
+        return $this;
+    }
+
+    /**
+     * Removes spaces from rgb(0, 0, 0) so that shorthand CSS properties work
+     * properly. THIS IS A HACK!
+     * @param string $string a CSS colour definition
+     * @return string
+     */
+    protected function mungeRgb($string)
+    {
+        return preg_replace('/rgb\((\d+)\s*,\s*(\d+)\s*,\s*(\d+)\)/', 'rgb(\1,\2,\3)', $string);
+    }
+
+    /**
+     * Parses a possibly escaped CSS string and returns the "pure"
+     * version of it.
+     */
+    protected function expandCSSEscape($string)
+    {
+        // flexibly parse it
+        $ret = '';
+        for ($i = 0, $c = strlen($string); $i < $c; $i++) {
+            if ($string[$i] === '\\') {
+                $i++;
+                if ($i >= $c) {
+                    $ret .= '\\';
+                    break;
+                }
+                if (ctype_xdigit($string[$i])) {
+                    $code = $string[$i];
+                    for ($a = 1, $i++; $i < $c && $a < 6; $i++, $a++) {
+                        if (!ctype_xdigit($string[$i])) {
+                            break;
+                        }
+                        $code .= $string[$i];
+                    }
+                    // We have to be extremely careful when adding
+                    // new characters, to make sure we're not breaking
+                    // the encoding.
+                    $char = HTMLPurifier_Encoder::unichr(hexdec($code));
+                    if (HTMLPurifier_Encoder::cleanUTF8($char) === '') {
+                        continue;
+                    }
+                    $ret .= $char;
+                    if ($i < $c && trim($string[$i]) !== '') {
+                        $i--;
+                    }
+                    continue;
+                }
+                if ($string[$i] === "\n") {
+                    continue;
+                }
+            }
+            $ret .= $string[$i];
+        }
+        return $ret;
+    }
+}
+
+// vim: et sw=4 sts=4