base::Time multiplicative operator overloading

Review URL: https://codereview.chromium.org/945143002

Cr-Commit-Position: refs/heads/master@{#317653}

base/time/time.h

@@ -158,34 +158,30 @@ class BASE_EXPORT TimeDelta {
     return TimeDelta(-delta_);
   }
 
-  // Computations with ints, note that we only allow multiplicative operations
-  // with ints, and additive operations with other deltas.
-  TimeDelta operator*(int64 a) const {
+  // Computations with numeric types.
+  template<typename T>
+  TimeDelta operator*(T a) const {
     return TimeDelta(delta_ * a);
   }
-  TimeDelta operator/(int64 a) const {
+  template<typename T>
+  TimeDelta operator/(T a) const {
     return TimeDelta(delta_ / a);
   }
-  TimeDelta& operator*=(int64 a) {
+  template<typename T>
+  TimeDelta& operator*=(T a) {
     delta_ *= a;
     return *this;
   }
-  TimeDelta& operator/=(int64 a) {
+  template<typename T>
+  TimeDelta& operator/=(T a) {
     delta_ /= a;
     return *this;
   }
+
   int64 operator/(TimeDelta a) const {
     return delta_ / a.delta_;
   }
 
-  // Multiplicative computations with floats.
-  TimeDelta multiply_by(double a) const {
-    return TimeDelta(delta_ * a);
-  }
-  TimeDelta divide_by(double a) const {
-    return TimeDelta(delta_ / a);
-  }
-
   // Defined below because it depends on the definition of the other classes.
   Time operator+(Time t) const;
   TimeTicks operator+(TimeTicks t) const;
@@ -213,7 +209,6 @@ class BASE_EXPORT TimeDelta {
  private:
   friend class Time;
   friend class TimeTicks;
-  friend TimeDelta operator*(int64 a, TimeDelta td);
 
   // Constructs a delta given the duration in microseconds. This is private
   // to avoid confusion by callers with an integer constructor. Use
@@ -225,8 +220,9 @@ class BASE_EXPORT TimeDelta {
   int64 delta_;
 };
 
-inline TimeDelta operator*(int64 a, TimeDelta td) {
-  return TimeDelta(a * td.delta_);
+template<typename T>
+inline TimeDelta operator*(T a, TimeDelta td) {
+  return td * a;
 }
 
 // For logging use only.

base/time/time_unittest.cc

@@ -868,12 +868,78 @@ TEST(TimeDelta, Magnitude) {
 }
 
 
-TEST(TimeDelta, multiply_by) {
+TEST(TimeDelta, NumericOperators) {
   double d = 0.5;
   EXPECT_EQ(TimeDelta::FromMilliseconds(500),
-            TimeDelta::FromMilliseconds(1000).multiply_by(d));
+            TimeDelta::FromMilliseconds(1000) * d);
   EXPECT_EQ(TimeDelta::FromMilliseconds(2000),
-            TimeDelta::FromMilliseconds(1000).divide_by(d));
+            TimeDelta::FromMilliseconds(1000) / d);
+  EXPECT_EQ(TimeDelta::FromMilliseconds(500),
+            TimeDelta::FromMilliseconds(1000) *= d);
+  EXPECT_EQ(TimeDelta::FromMilliseconds(2000),
+            TimeDelta::FromMilliseconds(1000) /= d);
+  EXPECT_EQ(TimeDelta::FromMilliseconds(500),
+            d * TimeDelta::FromMilliseconds(1000));
+
+  float f = 0.5;
+  EXPECT_EQ(TimeDelta::FromMilliseconds(500),
+            TimeDelta::FromMilliseconds(1000) * f);
+  EXPECT_EQ(TimeDelta::FromMilliseconds(2000),
+            TimeDelta::FromMilliseconds(1000) / f);
+  EXPECT_EQ(TimeDelta::FromMilliseconds(500),
+            TimeDelta::FromMilliseconds(1000) *= f);
+  EXPECT_EQ(TimeDelta::FromMilliseconds(2000),
+            TimeDelta::FromMilliseconds(1000) /= f);
+  EXPECT_EQ(TimeDelta::FromMilliseconds(500),
+            f * TimeDelta::FromMilliseconds(1000));
+
+
+  int i = 2;
+  EXPECT_EQ(TimeDelta::FromMilliseconds(2000),
+            TimeDelta::FromMilliseconds(1000) * i);
+  EXPECT_EQ(TimeDelta::FromMilliseconds(500),
+            TimeDelta::FromMilliseconds(1000) / i);
+  EXPECT_EQ(TimeDelta::FromMilliseconds(2000),
+            TimeDelta::FromMilliseconds(1000) *= i);
+  EXPECT_EQ(TimeDelta::FromMilliseconds(500),
+            TimeDelta::FromMilliseconds(1000) /= i);
+  EXPECT_EQ(TimeDelta::FromMilliseconds(2000),
+            i * TimeDelta::FromMilliseconds(1000));
+
+  int64_t i64 = 2;
+  EXPECT_EQ(TimeDelta::FromMilliseconds(2000),
+            TimeDelta::FromMilliseconds(1000) * i64);
+  EXPECT_EQ(TimeDelta::FromMilliseconds(500),
+            TimeDelta::FromMilliseconds(1000) / i64);
+  EXPECT_EQ(TimeDelta::FromMilliseconds(2000),
+            TimeDelta::FromMilliseconds(1000) *= i64);
+  EXPECT_EQ(TimeDelta::FromMilliseconds(500),
+            TimeDelta::FromMilliseconds(1000) /= i64);
+  EXPECT_EQ(TimeDelta::FromMilliseconds(2000),
+            i64 * TimeDelta::FromMilliseconds(1000));
+
+
+  EXPECT_EQ(TimeDelta::FromMilliseconds(500),
+            TimeDelta::FromMilliseconds(1000) * 0.5);
+  EXPECT_EQ(TimeDelta::FromMilliseconds(2000),
+            TimeDelta::FromMilliseconds(1000) / 0.5);
+  EXPECT_EQ(TimeDelta::FromMilliseconds(500),
+            TimeDelta::FromMilliseconds(1000) *= 0.5);
+  EXPECT_EQ(TimeDelta::FromMilliseconds(2000),
+            TimeDelta::FromMilliseconds(1000) /= 0.5);
+  EXPECT_EQ(TimeDelta::FromMilliseconds(500),
+            0.5 * TimeDelta::FromMilliseconds(1000));
+
+  EXPECT_EQ(TimeDelta::FromMilliseconds(2000),
+            TimeDelta::FromMilliseconds(1000) * 2);
+  EXPECT_EQ(TimeDelta::FromMilliseconds(500),
+            TimeDelta::FromMilliseconds(1000) / 2);
+  EXPECT_EQ(TimeDelta::FromMilliseconds(2000),
+            TimeDelta::FromMilliseconds(1000) *= 2);
+  EXPECT_EQ(TimeDelta::FromMilliseconds(500),
+            TimeDelta::FromMilliseconds(1000) /= 2);
+  EXPECT_EQ(TimeDelta::FromMilliseconds(2000),
+            2 * TimeDelta::FromMilliseconds(1000));
 }
 
 TEST(TimeDeltaLogging, DCheckEqCompiles) {

content/browser/dom_storage/dom_storage_area.cc

@@ -48,7 +48,7 @@ DOMStorageArea::RateLimiter::RateLimiter(size_t desired_rate,
 }
 
 base::TimeDelta DOMStorageArea::RateLimiter::ComputeTimeNeeded() const {
-  return time_quantum_.multiply_by(samples_ / rate_);
+  return time_quantum_ * (samples_ / rate_);
 }
 
 base::TimeDelta DOMStorageArea::RateLimiter::ComputeDelayNeeded(