Add new file option php_namespace. (#3162)

* Add new file option php_namespace.

Use this option to change the namespace of php generated classes.
Default is empty. When this option is empty, the package name will be
used for determining the namespace.

* Uncomment commented tests

* Revert gdb test change

* Update csharp descriptor.

* Add test for empty php_namespace.

1 files changed, 24 insertions, 0 deletions

diff --git a/php/src/Google/Protobuf/Internal/FileDescriptorProto.php b/php/src/Google/Protobuf/Internal/FileDescriptorProto.php
index 0363d9e9..b229522a 100644
--- a/php/src/Google/Protobuf/Internal/FileDescriptorProto.php
+++ b/php/src/Google/Protobuf/Internal/FileDescriptorProto.php
@@ -147,6 +147,8 @@ class FileDescriptorProto extends \Google\Protobuf\Internal\Message
         GPBUtil::checkString($var, True);
         $this->name = $var;
         $this->has_name = true;
+
+        return $this;
     }
 
     public function hasName()
@@ -178,6 +180,8 @@ class FileDescriptorProto extends \Google\Protobuf\Internal\Message
         GPBUtil::checkString($var, True);
         $this->package = $var;
         $this->has_package = true;
+
+        return $this;
     }
 
     public function hasPackage()
@@ -209,6 +213,8 @@ class FileDescriptorProto extends \Google\Protobuf\Internal\Message
         $arr = GPBUtil::checkRepeatedField($var, \Google\Protobuf\Internal\GPBType::STRING);
         $this->dependency = $arr;
         $this->has_dependency = true;
+
+        return $this;
     }
 
     public function hasDependency()
@@ -240,6 +246,8 @@ class FileDescriptorProto extends \Google\Protobuf\Internal\Message
         $arr = GPBUtil::checkRepeatedField($var, \Google\Protobuf\Internal\GPBType::INT32);
         $this->public_dependency = $arr;
         $this->has_public_dependency = true;
+
+        return $this;
     }
 
     public function hasPublicDependency()
@@ -273,6 +281,8 @@ class FileDescriptorProto extends \Google\Protobuf\Internal\Message
         $arr = GPBUtil::checkRepeatedField($var, \Google\Protobuf\Internal\GPBType::INT32);
         $this->weak_dependency = $arr;
         $this->has_weak_dependency = true;
+
+        return $this;
     }
 
     public function hasWeakDependency()
@@ -304,6 +314,8 @@ class FileDescriptorProto extends \Google\Protobuf\Internal\Message
         $arr = GPBUtil::checkRepeatedField($var, \Google\Protobuf\Internal\GPBType::MESSAGE, \Google\Protobuf\Internal\DescriptorProto::class);
         $this->message_type = $arr;
         $this->has_message_type = true;
+
+        return $this;
     }
 
     public function hasMessageType()
@@ -327,6 +339,8 @@ class FileDescriptorProto extends \Google\Protobuf\Internal\Message
         $arr = GPBUtil::checkRepeatedField($var, \Google\Protobuf\Internal\GPBType::MESSAGE, \Google\Protobuf\Internal\EnumDescriptorProto::class);
         $this->enum_type = $arr;
         $this->has_enum_type = true;
+
+        return $this;
     }
 
     public function hasEnumType()
@@ -350,6 +364,8 @@ class FileDescriptorProto extends \Google\Protobuf\Internal\Message
         $arr = GPBUtil::checkRepeatedField($var, \Google\Protobuf\Internal\GPBType::MESSAGE, \Google\Protobuf\Internal\ServiceDescriptorProto::class);
         $this->service = $arr;
         $this->has_service = true;
+
+        return $this;
     }
 
     public function hasService()
@@ -373,6 +389,8 @@ class FileDescriptorProto extends \Google\Protobuf\Internal\Message
         $arr = GPBUtil::checkRepeatedField($var, \Google\Protobuf\Internal\GPBType::MESSAGE, \Google\Protobuf\Internal\FieldDescriptorProto::class);
         $this->extension = $arr;
         $this->has_extension = true;
+
+        return $this;
     }
 
     public function hasExtension()
@@ -396,6 +414,8 @@ class FileDescriptorProto extends \Google\Protobuf\Internal\Message
         GPBUtil::checkMessage($var, \Google\Protobuf\Internal\FileOptions::class);
         $this->options = $var;
         $this->has_options = true;
+
+        return $this;
     }
 
     public function hasOptions()
@@ -433,6 +453,8 @@ class FileDescriptorProto extends \Google\Protobuf\Internal\Message
         GPBUtil::checkMessage($var, \Google\Protobuf\Internal\SourceCodeInfo::class);
         $this->source_code_info = $var;
         $this->has_source_code_info = true;
+
+        return $this;
     }
 
     public function hasSourceCodeInfo()
@@ -466,6 +488,8 @@ class FileDescriptorProto extends \Google\Protobuf\Internal\Message
         GPBUtil::checkString($var, True);
         $this->syntax = $var;
         $this->has_syntax = true;
+
+        return $this;
     }
 
     public function hasSyntax()