Optimizing compiler: remove unnecessary `explicit' keywords.

Change-Id: I5927fd92d53308c81e14edbd6e7d1c943bfa085b
diff --git a/compiler/optimizing/code_generator_arm.cc b/compiler/optimizing/code_generator_arm.cc
index 206ed13..d8e9dec 100644
--- a/compiler/optimizing/code_generator_arm.cc
+++ b/compiler/optimizing/code_generator_arm.cc
@@ -118,9 +118,9 @@
 
 class BoundsCheckSlowPathARM : public SlowPathCode {
  public:
-  explicit BoundsCheckSlowPathARM(HBoundsCheck* instruction,
-                                  Location index_location,
-                                  Location length_location)
+  BoundsCheckSlowPathARM(HBoundsCheck* instruction,
+                         Location index_location,
+                         Location length_location)
       : instruction_(instruction),
         index_location_(index_location),
         length_location_(length_location) {}
diff --git a/compiler/optimizing/code_generator_arm.h b/compiler/optimizing/code_generator_arm.h
index 0902fb8..81533c4 100644
--- a/compiler/optimizing/code_generator_arm.h
+++ b/compiler/optimizing/code_generator_arm.h
@@ -83,7 +83,7 @@
 
 class LocationsBuilderARM : public HGraphVisitor {
  public:
-  explicit LocationsBuilderARM(HGraph* graph, CodeGeneratorARM* codegen)
+  LocationsBuilderARM(HGraph* graph, CodeGeneratorARM* codegen)
       : HGraphVisitor(graph), codegen_(codegen) {}
 
 #define DECLARE_VISIT_INSTRUCTION(name)     \
diff --git a/compiler/optimizing/code_generator_x86.cc b/compiler/optimizing/code_generator_x86.cc
index 0db4311..2fcbc49 100644
--- a/compiler/optimizing/code_generator_x86.cc
+++ b/compiler/optimizing/code_generator_x86.cc
@@ -92,9 +92,9 @@
 
 class BoundsCheckSlowPathX86 : public SlowPathCode {
  public:
-  explicit BoundsCheckSlowPathX86(HBoundsCheck* instruction,
-                                  Location index_location,
-                                  Location length_location)
+  BoundsCheckSlowPathX86(HBoundsCheck* instruction,
+                         Location index_location,
+                         Location length_location)
       : instruction_(instruction), index_location_(index_location), length_location_(length_location) {}
 
   virtual void EmitNativeCode(CodeGenerator* codegen) OVERRIDE {
diff --git a/compiler/optimizing/code_generator_x86_64.cc b/compiler/optimizing/code_generator_x86_64.cc
index 56198af..4445333 100644
--- a/compiler/optimizing/code_generator_x86_64.cc
+++ b/compiler/optimizing/code_generator_x86_64.cc
@@ -121,9 +121,9 @@
 
 class BoundsCheckSlowPathX86_64 : public SlowPathCode {
  public:
-  explicit BoundsCheckSlowPathX86_64(HBoundsCheck* instruction,
-                                     Location index_location,
-                                     Location length_location)
+  BoundsCheckSlowPathX86_64(HBoundsCheck* instruction,
+                            Location index_location,
+                            Location length_location)
       : instruction_(instruction),
         index_location_(index_location),
         length_location_(length_location) {}
diff --git a/compiler/optimizing/locations.h b/compiler/optimizing/locations.h
index 06623b6..8c9d416 100644
--- a/compiler/optimizing/locations.h
+++ b/compiler/optimizing/locations.h
@@ -310,7 +310,7 @@
     kCall
   };
 
-  explicit LocationSummary(HInstruction* instruction, CallKind call_kind = kNoCall);
+  LocationSummary(HInstruction* instruction, CallKind call_kind = kNoCall);
 
   void SetInAt(uint32_t at, Location location) {
     inputs_.Put(at, location);
diff --git a/compiler/optimizing/nodes.h b/compiler/optimizing/nodes.h
index be6b355..e8d19f5 100644
--- a/compiler/optimizing/nodes.h
+++ b/compiler/optimizing/nodes.h
@@ -1271,7 +1271,7 @@
 // Load a given local. The local is an input of this instruction.
 class HLoadLocal : public HExpression<1> {
  public:
-  explicit HLoadLocal(HLocal* local, Primitive::Type type)
+  HLoadLocal(HLocal* local, Primitive::Type type)
       : HExpression(type, SideEffects::None()) {
     SetRawInputAt(0, local);
   }
@@ -1589,7 +1589,7 @@
 
 class FieldInfo : public ValueObject {
  public:
-  explicit FieldInfo(MemberOffset field_offset, Primitive::Type field_type)
+  FieldInfo(MemberOffset field_offset, Primitive::Type field_type)
       : field_offset_(field_offset), field_type_(field_type) {}
 
   MemberOffset GetFieldOffset() const { return field_offset_; }