Remove unnecessary `explicit` qualifiers on constructors.

Change-Id: Id12e392ad50f66a6e2251a68662b7959315dc567
diff --git a/compiler/optimizing/code_generator_mips64.cc b/compiler/optimizing/code_generator_mips64.cc
index b6ebeb4..4cee4a3 100644
--- a/compiler/optimizing/code_generator_mips64.cc
+++ b/compiler/optimizing/code_generator_mips64.cc
@@ -294,8 +294,7 @@
 
 class SuspendCheckSlowPathMIPS64 : public SlowPathCodeMIPS64 {
  public:
-  explicit SuspendCheckSlowPathMIPS64(HSuspendCheck* instruction,
-                                      HBasicBlock* successor)
+  SuspendCheckSlowPathMIPS64(HSuspendCheck* instruction, HBasicBlock* successor)
       : instruction_(instruction), successor_(successor) {}
 
   void EmitNativeCode(CodeGenerator* codegen) OVERRIDE {